diff --git a/src/lib_crawler/layer_1.ml b/src/lib_crawler/layer_1.ml
index 9c8d7eedf8ea8d0d216245329810d0faa399365b..70a128dec8325bca4d085d1151b4f6440337568e 100644
--- a/src/lib_crawler/layer_1.ml
+++ b/src/lib_crawler/layer_1.ml
@@ -229,18 +229,19 @@ let get_predecessor state ((hash, _) as head) =
   | None -> tzfail (Cannot_find_predecessor hash)
   | Some pred -> return pred
 
-let nth_predecessor l1_state n block =
+let nth_predecessor ~get_predecessor n block =
   let open Lwt_result_syntax in
   assert (n >= 0) ;
   let rec aux acc n block =
     if n = 0 then return (block, acc)
     else
-      let* pred = get_predecessor l1_state block in
+      let* pred = get_predecessor block in
       (aux [@tailcall]) (block :: acc) (n - 1) pred
   in
   aux [] n block
 
-let get_tezos_reorg_for_new_head l1_state old_head new_head =
+let get_tezos_reorg_for_new_head l1_state
+    ?(get_old_predecessor = get_predecessor l1_state) old_head new_head =
   let open Lwt_result_syntax in
   (* old_head and new_head must have the same level when calling aux *)
   let rec aux reorg old_head new_head =
@@ -248,7 +249,7 @@ let get_tezos_reorg_for_new_head l1_state old_head new_head =
     let new_head_hash, _ = new_head in
     if Block_hash.(old_head_hash = new_head_hash) then return reorg
     else
-      let* old_head_pred = get_predecessor l1_state old_head in
+      let* old_head_pred = get_old_predecessor old_head in
       let* new_head_pred = get_predecessor l1_state new_head in
       let reorg =
         Reorg.
@@ -268,17 +269,25 @@ let get_tezos_reorg_for_new_head l1_state old_head new_head =
     if old_head_level = new_head_level then
       return (old_head, new_head, Reorg.no_reorg)
     else if old_head_level < new_head_level then
-      let+ new_head, new_chain = nth_predecessor l1_state distance new_head in
+      let+ new_head, new_chain =
+        nth_predecessor
+          ~get_predecessor:(get_predecessor l1_state)
+          distance
+          new_head
+      in
       (old_head, new_head, {Reorg.no_reorg with new_chain})
     else
-      let+ old_head, old_chain = nth_predecessor l1_state distance old_head in
+      let+ old_head, old_chain =
+        nth_predecessor ~get_predecessor:get_old_predecessor distance old_head
+      in
       (old_head, new_head, {Reorg.no_reorg with old_chain})
   in
   assert (snd old_head = snd new_head) ;
   aux reorg old_head new_head
 
 (** Returns the reorganization of L1 blocks (if any) for [new_head]. *)
-let get_tezos_reorg_for_new_head l1_state old_head new_head =
+let get_tezos_reorg_for_new_head l1_state ?get_old_predecessor old_head new_head
+    =
   let open Lwt_result_syntax in
   match old_head with
   | `Level l ->
@@ -288,9 +297,14 @@ let get_tezos_reorg_for_new_head l1_state old_head new_head =
       else
         let* _block_at_l, new_chain =
           nth_predecessor
-            l1_state
+            ~get_predecessor:(get_predecessor l1_state)
             (Int32.sub new_head_level l |> Int32.to_int)
             new_head
         in
         return Reorg.{old_chain = []; new_chain}
-  | `Head old_head -> get_tezos_reorg_for_new_head l1_state old_head new_head
+  | `Head old_head ->
+      get_tezos_reorg_for_new_head
+        l1_state
+        ?get_old_predecessor
+        old_head
+        new_head
diff --git a/src/lib_crawler/layer_1.mli b/src/lib_crawler/layer_1.mli
index f3f549bc551d696fee053555a73b18244993c418..e03581a8734d54af6c86ab7ed45882b6dc373491 100644
--- a/src/lib_crawler/layer_1.mli
+++ b/src/lib_crawler/layer_1.mli
@@ -27,6 +27,8 @@
 (** This module allow to follow the layer 1 chain by subscribing to the head
     monitoring RPC offered by the Tezos node, reconnecting, etc. *)
 
+type error += Cannot_find_predecessor of Block_hash.t
+
 (** The type of layer 1 followers. *)
 type t
 
@@ -66,21 +68,28 @@ val get_predecessor_opt :
 val get_predecessor :
   t -> Block_hash.t * int32 -> (Block_hash.t * int32) tzresult Lwt.t
 
-(** [nth_predecessor l1_ctxt n head] returns [block, history] where [block] is
-    the nth predecessor of [head] and [history] is the list of blocks between
-    [block] (excluded) and [head] (included) on the chain *)
+(** [nth_predecessor ~get_predecessor n head] returns [block, history] where
+    [block] is the nth predecessor of [head] and [history] is the list of blocks
+    between [block] (excluded) and [head] (included) on the chain. It uses the
+    function [get_predecessor] to retrieve the predecessor of one block. *)
 val nth_predecessor :
-  t ->
+  get_predecessor:('a -> 'a tzresult Lwt.t) ->
   int ->
-  Block_hash.t * int32 ->
-  ((Block_hash.t * int32) * (Block_hash.t * int32) list) tzresult Lwt.t
+  'a ->
+  ('a * 'a trace) tzresult Lwt.t
 
-(** [get_tezos_reorg_for_new_head l1_ctxt old_head new_head] returns the
-    reorganization of L1 blocks between [old_head] and [new_head]. If [old_head]
-    is [`Level l], then it returns the reorganization between [new_head] and
-    level [l] on the same chain. *)
+(** [get_tezos_reorg_for_new_head l1_ctxt ?get_old_predecessor old_head
+    new_head] returns the reorganization of L1 blocks between [old_head] and
+    [new_head]. If [old_head] is [`Level l], then it returns the reorganization
+    between [new_head] and level [l] on the same chain. [get_old_predecessor]
+    can be provided to use a different function (than by default
+    {!get_predecessor}) to retrieve the predecessors of the old head. This is
+    necessary when the old head is not in the L1 chain anymore and forgotten by
+    the L1 node. *)
 val get_tezos_reorg_for_new_head :
   t ->
+  ?get_old_predecessor:
+    (Block_hash.t * int32 -> (Block_hash.t * int32) tzresult Lwt.t) ->
   [`Head of Block_hash.t * int32 | `Level of int32] ->
   Block_hash.t * int32 ->
   (Block_hash.t * int32) Reorg.t tzresult Lwt.t
diff --git a/src/lib_injector/injector_events.ml b/src/lib_injector/injector_events.ml
index acc4a3d134b1db7bef4acf50c01721f546332484..ff6ff1062819155ff3fc2a4850fbbb7eeb7b6098 100644
--- a/src/lib_injector/injector_events.ml
+++ b/src/lib_injector/injector_events.ml
@@ -129,6 +129,13 @@ module Make
           ~level:Debug
           ("head", Block_hash.encoding)
 
+      let cannot_compute_reorg =
+        declare_1
+          ~name:"cannot_compute_reorg"
+          ~msg:"Cannot compute reorg for new block {head}"
+          ~level:Warning
+          ("head", Block_hash.encoding)
+
       let injecting_pending =
         declare_1
           ~name:"injecting_pending"
diff --git a/src/lib_injector/injector_functor.ml b/src/lib_injector/injector_functor.ml
index 884284926019a6d203bd1633d3a615fde965ec96..729265213423d7d5ca85cae14edb2a8548178c5b 100644
--- a/src/lib_injector/injector_functor.ml
+++ b/src/lib_injector/injector_functor.ml
@@ -922,7 +922,7 @@ struct
   let on_new_tezos_head state ((head_hash, head_level) as head) =
     let open Lwt_result_syntax in
     let*! () = Event.(emit1 new_tezos_head) state head_hash in
-    let* reorg =
+    let*! reorg =
       match state.last_seen_head with
       | None -> return {Reorg.no_reorg with new_chain = [head]}
       | Some last_head ->
@@ -931,6 +931,25 @@ struct
             (`Head last_head)
             head
     in
+    let* reorg =
+      match reorg with
+      | Error trace
+        when TzTrace.fold
+               (fun yes error ->
+                 yes
+                 ||
+                 match error with
+                 | Layer_1.Cannot_find_predecessor _ -> true
+                 | _ -> false)
+               false
+               trace ->
+          (* The reorganization could not be computed entirely because of
+             missing info on the Layer 1. We may miss on some backtracking but
+             it is better than to fail. *)
+          let*! () = Event.(emit1 cannot_compute_reorg) state head_hash in
+          return {Reorg.no_reorg with new_chain = [head]}
+      | _ -> Lwt.return reorg
+    in
     let* () =
       List.iter_es
         (fun (removed_block, _) ->
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/daemon.ml b/src/proto_016_PtMumbai/lib_sc_rollup_node/daemon.ml
index f824fd99cf8ddeee08ee603c5bf3d6f662ef3583..9f067c83c4a4154f1d852c84713af9471e53b2a7 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/daemon.ml
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/daemon.ml
@@ -299,7 +299,7 @@ module Make (PVM : Pvm.S) = struct
     in
     unless (already_finalized || before_origination node_ctxt block)
     @@ fun () ->
-    let* predecessor = Layer1.get_predecessor_opt node_ctxt.l1_ctxt block in
+    let* predecessor = Node_context.get_predecessor_opt node_ctxt block in
     let* () =
       Option.iter_es (processed_finalized_block node_ctxt) predecessor
     in
@@ -308,69 +308,85 @@ module Make (PVM : Pvm.S) = struct
     let* () = Node_context.mark_finalized_head node_ctxt hash in
     return_unit
 
-  let process_head (node_ctxt : _ Node_context.t) Layer1.({hash; level} as head)
-      =
+  let rec process_head (node_ctxt : _ Node_context.t)
+      Layer1.({hash; level} as head) =
     let open Lwt_result_syntax in
+    let* already_processed = Node_context.is_processed node_ctxt hash in
+    unless (already_processed || before_origination node_ctxt head) @@ fun () ->
     let*! () = Daemon_event.head_processing hash level ~finalized:false in
-    let* () = Node_context.save_level node_ctxt head in
-    let* inbox_hash, inbox, inbox_witness, messages, ctxt =
-      Inbox.process_head node_ctxt head
-    in
-    let* () =
-      when_ (Node_context.dal_supported node_ctxt) @@ fun () ->
-      Dal_slots_tracker.process_head node_ctxt head
-    in
-    let* () = process_l1_block_operations ~finalized:false node_ctxt head in
-    (* Avoid storing and publishing commitments if the head is not final. *)
-    (* Avoid triggering the pvm execution if this has been done before for
-       this head. *)
-    let* ctxt, _num_messages, num_ticks, initial_tick =
-      Components.Interpreter.process_head node_ctxt ctxt head (inbox, messages)
-    in
-    let*! context_hash = Context.commit ctxt in
-    let* {Layer1.hash = predecessor; _} =
-      Layer1.get_predecessor node_ctxt.l1_ctxt head
-    in
-    let* commitment_hash =
-      Components.Commitment.process_head node_ctxt ~predecessor head ctxt
-    in
-    let level = Raw_level.of_int32_exn level in
-    let* previous_commitment_hash =
-      if level = node_ctxt.genesis_info.Sc_rollup.Commitment.level then
-        (* Previous commitment for rollup genesis is itself. *)
-        return node_ctxt.genesis_info.Sc_rollup.Commitment.commitment_hash
-      else
-        let+ pred = Node_context.get_l2_block node_ctxt predecessor in
-        Sc_rollup_block.most_recent_commitment pred.header
-    in
-    let header =
-      Sc_rollup_block.
-        {
-          block_hash = hash;
-          level;
-          predecessor;
-          commitment_hash;
-          previous_commitment_hash;
-          context = context_hash;
-          inbox_witness;
-          inbox_hash;
-        }
-    in
-    let l2_block =
-      Sc_rollup_block.{header; content = (); num_ticks; initial_tick}
-    in
-    let* finalized_block, _ =
-      Layer1.nth_predecessor
-        node_ctxt.l1_ctxt
-        node_ctxt.block_finality_time
-        head
-    in
-    let* () = processed_finalized_block node_ctxt finalized_block in
-    let* () = Node_context.save_l2_head node_ctxt l2_block in
-    let*! () =
-      Daemon_event.new_head_processed hash (Raw_level.to_int32 level)
-    in
-    return_unit
+    let* predecessor = Node_context.get_predecessor_opt node_ctxt head in
+    match predecessor with
+    | None ->
+        (* Predecessor not available on the L1, which means the block does not
+           exist in the chain. *)
+        return_unit
+    | Some predecessor ->
+        let* () = process_head node_ctxt predecessor in
+        let* () = Node_context.save_level node_ctxt head in
+        let* inbox_hash, inbox, inbox_witness, messages, ctxt =
+          Inbox.process_head node_ctxt ~predecessor head
+        in
+        let* () =
+          when_ (Node_context.dal_supported node_ctxt) @@ fun () ->
+          Dal_slots_tracker.process_head node_ctxt head
+        in
+        let* () = process_l1_block_operations ~finalized:false node_ctxt head in
+        (* Avoid storing and publishing commitments if the head is not final. *)
+        (* Avoid triggering the pvm execution if this has been done before for
+           this head. *)
+        let* ctxt, _num_messages, num_ticks, initial_tick =
+          Components.Interpreter.process_head
+            node_ctxt
+            ctxt
+            ~predecessor
+            head
+            (inbox, messages)
+        in
+        let*! context_hash = Context.commit ctxt in
+        let* commitment_hash =
+          Components.Commitment.process_head
+            node_ctxt
+            ~predecessor:predecessor.hash
+            head
+            ctxt
+        in
+        let level = Raw_level.of_int32_exn level in
+        let* previous_commitment_hash =
+          if level = node_ctxt.genesis_info.Sc_rollup.Commitment.level then
+            (* Previous commitment for rollup genesis is itself. *)
+            return node_ctxt.genesis_info.Sc_rollup.Commitment.commitment_hash
+          else
+            let+ pred = Node_context.get_l2_block node_ctxt predecessor.hash in
+            Sc_rollup_block.most_recent_commitment pred.header
+        in
+        let header =
+          Sc_rollup_block.
+            {
+              block_hash = hash;
+              level;
+              predecessor = predecessor.hash;
+              commitment_hash;
+              previous_commitment_hash;
+              context = context_hash;
+              inbox_witness;
+              inbox_hash;
+            }
+        in
+        let l2_block =
+          Sc_rollup_block.{header; content = (); num_ticks; initial_tick}
+        in
+        let* finalized_block, _ =
+          Node_context.nth_predecessor
+            node_ctxt
+            node_ctxt.block_finality_time
+            head
+        in
+        let* () = processed_finalized_block node_ctxt finalized_block in
+        let* () = Node_context.save_l2_head node_ctxt l2_block in
+        let*! () =
+          Daemon_event.new_head_processed hash (Raw_level.to_int32 level)
+        in
+        return_unit
 
   (* [on_layer_1_head node_ctxt head] processes a new head from the L1. It
      also processes any missing blocks that were not processed. Every time a
@@ -396,8 +412,25 @@ module Make (PVM : Pvm.S) = struct
           in
           `Level (Int32.pred origination_level)
     in
-    let* reorg =
-      Layer1.get_tezos_reorg_for_new_head node_ctxt.l1_ctxt old_head head
+    let*! reorg =
+      Node_context.get_tezos_reorg_for_new_head node_ctxt old_head head
+    in
+    let*? reorg =
+      match reorg with
+      | Error trace
+        when TzTrace.fold
+               (fun yes error ->
+                 yes
+                 ||
+                 match error with
+                 | Octez_crawler.Layer_1.Cannot_find_predecessor _ -> true
+                 | _ -> false)
+               false
+               trace ->
+          (* The reorganization could not be computed entirely because of missing
+             info on the Layer 1. We fallback to a recursive process_head. *)
+          Ok {Reorg.no_reorg with new_chain = [head]}
+      | _ -> reorg
     in
     (* TODO: https://gitlab.com/tezos/tezos/-/issues/3348
        Rollback state information on reorganization, i.e. for
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/dal_slots_tracker.ml b/src/proto_016_PtMumbai/lib_sc_rollup_node/dal_slots_tracker.ml
index 26239d7de02276888fa6ae2fffb1d5470f83282d..e1469af4c414cd54e18a9e750b056a0ec3816548 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/dal_slots_tracker.ml
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/dal_slots_tracker.ml
@@ -27,15 +27,15 @@ open Protocol
 open Alpha_context
 module Block_services = Block_services.Make (Protocol) (Protocol)
 
-let ancestor_hash ~number_of_levels {Node_context.genesis_info; l1_ctxt; _} head
-    =
+let ancestor_hash ~number_of_levels
+    ({Node_context.genesis_info; _} as node_ctxt) head =
   let genesis_level = genesis_info.level in
   let rec go number_of_levels (Layer1.{hash; level} as head) =
     let open Lwt_result_syntax in
     if level < Raw_level.to_int32 genesis_level then return_none
     else if number_of_levels = 0 then return_some hash
     else
-      let* pred_head = Layer1.get_predecessor_opt l1_ctxt head in
+      let* pred_head = Node_context.get_predecessor_opt node_ctxt head in
       match pred_head with
       | None -> return_none
       | Some pred_head -> go (number_of_levels - 1) pred_head
@@ -320,8 +320,8 @@ module Confirmed_slots_history = struct
         @@ Dal.Slots_history.History_cache.empty
              ~capacity:(Int64.of_int @@ (num_slots * 60000)))
 
-  let update (Node_context.{l1_ctxt; _} as node_ctxt)
-      Layer1.({hash = head_hash; _} as head) confirmation_info =
+  let update node_ctxt Layer1.({hash = head_hash; _} as head) confirmation_info
+      =
     let open Lwt_result_syntax in
     let* slots_to_save =
       confirmed_slots_with_headers node_ctxt confirmation_info
@@ -333,7 +333,7 @@ module Confirmed_slots_history = struct
           Slot_index.compare a b)
         slots_to_save
     in
-    let* pred = Layer1.get_predecessor l1_ctxt head in
+    let* pred = Node_context.get_predecessor node_ctxt head in
     let* slots_history = slots_history_of_hash node_ctxt pred in
     let* slots_cache = slots_history_cache_of_hash node_ctxt pred in
     let*? slots_history, slots_cache =
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/inbox.ml b/src/proto_016_PtMumbai/lib_sc_rollup_node/inbox.ml
index 572791baf5c3a159007d28fbb059b3b704b7b466..e788af5f0d550f289876f366d56bac152667540a 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/inbox.ml
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/inbox.ml
@@ -120,8 +120,8 @@ let add_messages ~predecessor_timestamp ~predecessor inbox messages =
          inbox,
          messages_with_protocol_internal_messages )
 
-let process_head (node_ctxt : _ Node_context.t)
-    Layer1.({level; hash = head_hash} as head) =
+let process_head (node_ctxt : _ Node_context.t) ~predecessor
+    Layer1.{level; hash = head_hash} =
   let open Lwt_result_syntax in
   let first_inbox_level =
     Raw_level.to_int32 node_ctxt.genesis_info.level |> Int32.succ
@@ -134,7 +134,6 @@ let process_head (node_ctxt : _ Node_context.t)
           to chain reorganization.
 
     *)
-    let* predecessor = Layer1.get_predecessor node_ctxt.l1_ctxt head in
     let* inbox = Node_context.inbox_of_head node_ctxt predecessor in
     let inbox_metrics = Metrics.Inbox.metrics in
     Prometheus.Gauge.set inbox_metrics.head_inbox_level @@ Int32.to_float level ;
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/inbox.mli b/src/proto_016_PtMumbai/lib_sc_rollup_node/inbox.mli
index f1b33285c0769b4c631d2d2ee2717a2822b9b010..b078741d65da8da37bb05efa8aa77558e9586255 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/inbox.mli
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/inbox.mli
@@ -36,11 +36,13 @@
 open Protocol.Alpha_context
 open Sc_rollup
 
-(** [process_head node_ctxt head operations] changes the state of the inbox to
-    react to [head]. In particular, this process filters the provided
+(** [process_head node_ctxt ~predecessor head operations] changes the state of
+    the inbox to react to [head] (where [predecessor] is the predecessor of
+    [head] in the L1 chain). In particular, this process filters the provided
     [operations] of the [head] block. *)
 val process_head :
   Node_context.rw ->
+  predecessor:Layer1.head ->
   Layer1.head ->
   (Sc_rollup.Inbox.Hash.t
   * Sc_rollup.Inbox.t
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/interpreter.ml b/src/proto_016_PtMumbai/lib_sc_rollup_node/interpreter.ml
index 47242dd61817eff65379d72fe856eeb0c24fde7b..f74691dd333627f70222a95456528b04a351ed23 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/interpreter.ml
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/interpreter.ml
@@ -38,6 +38,7 @@ module type S = sig
   val process_head :
     Node_context.rw ->
     'a Context.t ->
+    predecessor:Layer1.head ->
     Layer1.head ->
     Sc_rollup.Inbox.t * Sc_rollup.Inbox_message.t list ->
     ('a Context.t * int * int64 * Sc_rollup.Tick.t) tzresult Lwt.t
@@ -162,16 +163,15 @@ module Make (PVM : Pvm.S) : S with module PVM = PVM = struct
     in
     return (ctxt, num_messages, num_ticks, initial_tick)
 
-  (** [process_head node_ctxt head] runs the PVM for the given head. *)
-  let process_head (node_ctxt : _ Node_context.t) ctxt head inbox_messages =
+  (** [process_head node_ctxt ctxt ~predecessor head] runs the PVM for the given
+      head. *)
+  let process_head (node_ctxt : _ Node_context.t) ctxt ~predecessor head
+      inbox_messages =
     let open Lwt_result_syntax in
     let first_inbox_level =
       Raw_level.to_int32 node_ctxt.genesis_info.level |> Int32.succ
     in
     if head.Layer1.level >= first_inbox_level then
-      let* predecessor =
-        Layer1.get_predecessor node_ctxt.Node_context.l1_ctxt head
-      in
       transition_pvm node_ctxt ctxt predecessor head inbox_messages
     else if head.Layer1.level = Raw_level.to_int32 node_ctxt.genesis_info.level
     then
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/interpreter.mli b/src/proto_016_PtMumbai/lib_sc_rollup_node/interpreter.mli
index 18281abb76f28d17fec42853273ca1f28d9aaa93..71cdbcabd249910063015f09d45fc8b4219353f3 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/interpreter.mli
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/interpreter.mli
@@ -34,16 +34,18 @@ module type S = sig
   module Free_pvm :
     Fueled_pvm.S with module PVM = PVM and type fuel = Fuel.Free.t
 
-  (** [process_head node_ctxt head (inbox, messages)] interprets the [messages]
-      associated with a [head]. This requires the [inbox] to be updated
-      beforehand. It returns [(ctxt, num_messages, num_ticks, tick)] where
-      [ctxt] is the updated layer 2 context (with the new PVM state),
+  (** [process_head node_ctxt ~predecessor head (inbox, messages)] interprets
+      the [messages] associated with a [head] (where [predecessor] is the
+      predecessor of [head] in the L1 chain). This requires the [inbox] to be
+      updated beforehand. It returns [(ctxt, num_messages, num_ticks, tick)]
+      where [ctxt] is the updated layer 2 context (with the new PVM state),
       [num_messages] is the number of [messages], [num_ticks] is the number of
       ticks taken by the PVM for the evaluation and [tick] is the tick reached
       by the PVM after the evaluation. *)
   val process_head :
     Node_context.rw ->
     'a Context.t ->
+    predecessor:Layer1.head ->
     Layer1.head ->
     Sc_rollup.Inbox.t * Sc_rollup.Inbox_message.t list ->
     ('a Context.t * int * int64 * Sc_rollup.Tick.t) tzresult Lwt.t
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/layer1.ml b/src/proto_016_PtMumbai/lib_sc_rollup_node/layer1.ml
index d11aa61d64c00e7f5974c871508f410e27247098..0c515602b8c258546bf1c156b0b6b6d2ae7bb263 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/layer1.ml
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/layer1.ml
@@ -78,40 +78,9 @@ let blocks_cache : blocks_cache = Blocks_cache.create 32
 
 include Octez_crawler.Layer_1
 
-let head_of_block_level (hash, level) = {hash; level}
-
-let block_level_of_head {hash; level} = (hash, level)
-
 let iter_heads l1_ctxt f =
   iter_heads l1_ctxt @@ fun (hash, {shell = {level; _}; _}) -> f {hash; level}
 
-let get_predecessor_opt state head =
-  let open Lwt_result_syntax in
-  let+ res = get_predecessor_opt state (block_level_of_head head) in
-  Option.map head_of_block_level res
-
-let get_predecessor state head =
-  let open Lwt_result_syntax in
-  let+ res = get_predecessor state (block_level_of_head head) in
-  head_of_block_level res
-
-let nth_predecessor l1_state n block =
-  let open Lwt_result_syntax in
-  let+ res, preds = nth_predecessor l1_state n (block_level_of_head block) in
-  (head_of_block_level res, List.map head_of_block_level preds)
-
-let get_tezos_reorg_for_new_head l1_ctxt old_head new_head =
-  let open Lwt_result_syntax in
-  let old_head =
-    match old_head with
-    | `Level l -> `Level l
-    | `Head h -> `Head (block_level_of_head h)
-  in
-  let+ reorg =
-    get_tezos_reorg_for_new_head l1_ctxt old_head (block_level_of_head new_head)
-  in
-  Reorg.map head_of_block_level reorg
-
 (**
 
    Helpers
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/layer1.mli b/src/proto_016_PtMumbai/lib_sc_rollup_node/layer1.mli
index 1580d1b26f023c61852796180b044bdbc0fbd25f..c9697e4fe5c0eae830ca054d187a4db7489a3f50 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/layer1.mli
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/layer1.mli
@@ -47,25 +47,6 @@ val iter_heads : t -> (head -> unit tzresult Lwt.t) -> unit tzresult Lwt.t
 
 (** {2 Helpers } *)
 
-(** [get_predecessor_opt state head] returns the predecessor of block [head],
-    when [head] is not the genesis block. *)
-val get_predecessor_opt : t -> head -> head option tzresult Lwt.t
-
-(** [get_predecessor state head] returns the predecessor block of [head]. *)
-val get_predecessor : t -> head -> head tzresult Lwt.t
-
-(** [nth_predecessor l1_ctxt n head] return [block, history] where [block] is
-    the nth predecessor of [head] and [history] is the list of blocks between
-    [block] (excluded) and [head] (included) on the chain *)
-val nth_predecessor : t -> int -> head -> (head * head list) tzresult Lwt.t
-
-(** [get_tezos_reorg_for_new_head l1_ctxt old_head new_head] returns the
-    reorganization of L1 blocks between [old_head] and [new_head]. If [old_head]
-    is [`Level l], then it returns the reorganization between [new_head] and
-    level [l] on the same chain. *)
-val get_tezos_reorg_for_new_head :
-  t -> [`Head of head | `Level of int32] -> head -> head Reorg.t tzresult Lwt.t
-
 (** [fetch_tezos_shell_header cctxt hash] returns the block shell header of
     [hash]. Looks for the block in the blocks cache first, and fetches it from
     the L1 node otherwise. *)
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/node_context.ml b/src/proto_016_PtMumbai/lib_sc_rollup_node/node_context.ml
index d17a6af774ad525aa46b1537490890da8d82db48..6f99993ff62faa058ae77230879bf57b6f10ee74 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/node_context.ml
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/node_context.ml
@@ -1,7 +1,8 @@
 (*****************************************************************************)
 (*                                                                           *)
 (* Open Source License                                                       *)
-(* Copyright (c) 2022 TriliTech <contact@trili.tech>                         *)
+(* Copyright (c) 2023 TriliTech <contact@trili.tech>                         *)
+(* Copyright (c) 2023 Functori, <contact@functori.com>                       *)
 (*                                                                           *)
 (* Permission is hereby granted, free of charge, to any person obtaining a   *)
 (* copy of this software and associated documentation files (the "Software"),*)
@@ -330,6 +331,72 @@ let find_l2_block_by_level node_ctxt level =
   | None -> return_none
   | Some block_hash -> find_l2_block node_ctxt block_hash
 
+let head_of_block_level (hash, level) = {Layer1.hash; level}
+
+let block_level_of_head Layer1.{hash; level} = (hash, level)
+
+let get_l2_block_predecessor node_ctxt hash =
+  let open Lwt_result_syntax in
+  let+ header = Store.L2_blocks.header node_ctxt.store.l2_blocks hash in
+  Option.map
+    (fun {Sc_rollup_block.predecessor; level; _} ->
+      (predecessor, Int32.pred (Raw_level.to_int32 level)))
+    header
+
+let get_predecessor_opt node_ctxt (hash, level) =
+  let open Lwt_result_syntax in
+  let* pred = get_l2_block_predecessor node_ctxt hash in
+  match pred with
+  | Some p -> return_some p
+  | None ->
+      (* [head] is not already known in the L2 chain *)
+      Layer1.get_predecessor_opt node_ctxt.l1_ctxt (hash, level)
+
+let get_predecessor node_ctxt (hash, level) =
+  let open Lwt_result_syntax in
+  let* pred = get_l2_block_predecessor node_ctxt hash in
+  match pred with
+  | Some p -> return p
+  | None ->
+      (* [head] is not already known in the L2 chain *)
+      Layer1.get_predecessor node_ctxt.l1_ctxt (hash, level)
+
+let nth_predecessor node_ctxt n block =
+  let open Lwt_result_syntax in
+  let+ res, preds =
+    Layer1.nth_predecessor
+      ~get_predecessor:(get_predecessor node_ctxt)
+      n
+      (block_level_of_head block)
+  in
+  (head_of_block_level res, List.map head_of_block_level preds)
+
+let get_tezos_reorg_for_new_head node_ctxt old_head new_head =
+  let open Lwt_result_syntax in
+  let old_head =
+    match old_head with
+    | `Level l -> `Level l
+    | `Head h -> `Head (block_level_of_head h)
+  in
+  let+ reorg =
+    Layer1.get_tezos_reorg_for_new_head
+      node_ctxt.l1_ctxt
+      ~get_old_predecessor:(get_predecessor node_ctxt)
+      old_head
+      (block_level_of_head new_head)
+  in
+  Reorg.map head_of_block_level reorg
+
+let get_predecessor_opt node_ctxt head =
+  let open Lwt_result_syntax in
+  let+ res = get_predecessor_opt node_ctxt (block_level_of_head head) in
+  Option.map head_of_block_level res
+
+let get_predecessor node_ctxt head =
+  let open Lwt_result_syntax in
+  let+ res = get_predecessor node_ctxt (block_level_of_head head) in
+  head_of_block_level res
+
 (* TODO: https://gitlab.com/tezos/tezos/-/issues/4128
    Unit test the function tick_search. *)
 
diff --git a/src/proto_016_PtMumbai/lib_sc_rollup_node/node_context.mli b/src/proto_016_PtMumbai/lib_sc_rollup_node/node_context.mli
index 5d896e7faa78b50056f57531252f5690f5c176f2..1f976a65d56062dbc8c1b4df207a3791d3b5f25c 100644
--- a/src/proto_016_PtMumbai/lib_sc_rollup_node/node_context.mli
+++ b/src/proto_016_PtMumbai/lib_sc_rollup_node/node_context.mli
@@ -1,7 +1,8 @@
 (*****************************************************************************)
 (*                                                                           *)
 (* Open Source License                                                       *)
-(* Copyright (c) 2022 TriliTech <contact@trili.tech>                         *)
+(* Copyright (c) 2023 TriliTech <contact@trili.tech>                         *)
+(* Copyright (c) 2023 Functori, <contact@functori.com>                       *)
 (*                                                                           *)
 (* Permission is hereby granted, free of charge, to any person obtaining a   *)
 (* copy of this software and associated documentation files (the "Software"),*)
@@ -196,6 +197,28 @@ val hash_of_level_opt : _ t -> int32 -> Block_hash.t option tzresult Lwt.t
     if it is known by the Tezos Layer 1 node. *)
 val level_of_hash : _ t -> Block_hash.t -> int32 tzresult Lwt.t
 
+(** [get_predecessor_opt state head] returns the predecessor of block [head],
+    when [head] is not the genesis block. *)
+val get_predecessor_opt :
+  _ t -> Layer1.head -> Layer1.head option tzresult Lwt.t
+
+(** [get_predecessor state head] returns the predecessor block of [head]. *)
+val get_predecessor : _ t -> Layer1.head -> Layer1.head tzresult Lwt.t
+
+(** [nth_predecessor n head] return [block, history] where [block] is the nth
+    predecessor of [head] and [history] is the list of blocks between [block]
+    (excluded) and [head] (included) on the chain. *)
+val nth_predecessor :
+  _ t -> int -> Layer1.head -> (Layer1.head * Layer1.head list) tzresult Lwt.t
+
+(** [get_tezos_reorg_for_new_head node_ctxt old_head new_head] returns the L1
+    reorganization between [old_head] and [new_head]. *)
+val get_tezos_reorg_for_new_head :
+  _ t ->
+  [`Head of Layer1.head | `Level of int32] ->
+  Layer1.head ->
+  Layer1.head Reorg.t tzresult Lwt.t
+
 (** [block_with_tick store ~max_level tick] returns [Some b] where [b] is the
     last layer 2 block which contains the [tick] before [max_level]. If no such
     block exists (the tick happened after [max_level], or we are too late), the
diff --git a/src/proto_alpha/lib_sc_rollup_node/daemon.ml b/src/proto_alpha/lib_sc_rollup_node/daemon.ml
index 8c9fd495a64d1aba67aab9573913a3999d793e4b..6c40166adcd20200092a7010db52470b3eb9b679 100644
--- a/src/proto_alpha/lib_sc_rollup_node/daemon.ml
+++ b/src/proto_alpha/lib_sc_rollup_node/daemon.ml
@@ -296,7 +296,7 @@ module Make (PVM : Pvm.S) = struct
     in
     unless (already_finalized || before_origination node_ctxt block)
     @@ fun () ->
-    let* predecessor = Layer1.get_predecessor_opt node_ctxt.l1_ctxt block in
+    let* predecessor = Node_context.get_predecessor_opt node_ctxt block in
     let* () =
       Option.iter_es (processed_finalized_block node_ctxt) predecessor
     in
@@ -305,69 +305,85 @@ module Make (PVM : Pvm.S) = struct
     let* () = Node_context.mark_finalized_head node_ctxt hash in
     return_unit
 
-  let process_head (node_ctxt : _ Node_context.t) Layer1.({hash; level} as head)
-      =
+  let rec process_head (node_ctxt : _ Node_context.t)
+      Layer1.({hash; level} as head) =
     let open Lwt_result_syntax in
+    let* already_processed = Node_context.is_processed node_ctxt hash in
+    unless (already_processed || before_origination node_ctxt head) @@ fun () ->
     let*! () = Daemon_event.head_processing hash level ~finalized:false in
-    let* () = Node_context.save_level node_ctxt head in
-    let* inbox_hash, inbox, inbox_witness, messages, ctxt =
-      Inbox.process_head node_ctxt head
-    in
-    let* () =
-      when_ (Node_context.dal_supported node_ctxt) @@ fun () ->
-      Dal_slots_tracker.process_head node_ctxt head
-    in
-    let* () = process_l1_block_operations ~finalized:false node_ctxt head in
-    (* Avoid storing and publishing commitments if the head is not final. *)
-    (* Avoid triggering the pvm execution if this has been done before for
-       this head. *)
-    let* ctxt, _num_messages, num_ticks, initial_tick =
-      Components.Interpreter.process_head node_ctxt ctxt head (inbox, messages)
-    in
-    let*! context_hash = Context.commit ctxt in
-    let* {Layer1.hash = predecessor; _} =
-      Layer1.get_predecessor node_ctxt.l1_ctxt head
-    in
-    let* commitment_hash =
-      Components.Commitment.process_head node_ctxt ~predecessor head ctxt
-    in
-    let level = Raw_level.of_int32_exn level in
-    let* previous_commitment_hash =
-      if level = node_ctxt.genesis_info.Sc_rollup.Commitment.level then
-        (* Previous commitment for rollup genesis is itself. *)
-        return node_ctxt.genesis_info.Sc_rollup.Commitment.commitment_hash
-      else
-        let+ pred = Node_context.get_l2_block node_ctxt predecessor in
-        Sc_rollup_block.most_recent_commitment pred.header
-    in
-    let header =
-      Sc_rollup_block.
-        {
-          block_hash = hash;
-          level;
-          predecessor;
-          commitment_hash;
-          previous_commitment_hash;
-          context = context_hash;
-          inbox_witness;
-          inbox_hash;
-        }
-    in
-    let l2_block =
-      Sc_rollup_block.{header; content = (); num_ticks; initial_tick}
-    in
-    let* finalized_block, _ =
-      Layer1.nth_predecessor
-        node_ctxt.l1_ctxt
-        node_ctxt.block_finality_time
-        head
-    in
-    let* () = processed_finalized_block node_ctxt finalized_block in
-    let* () = Node_context.save_l2_head node_ctxt l2_block in
-    let*! () =
-      Daemon_event.new_head_processed hash (Raw_level.to_int32 level)
-    in
-    return_unit
+    let* predecessor = Node_context.get_predecessor_opt node_ctxt head in
+    match predecessor with
+    | None ->
+        (* Predecessor not available on the L1, which means the block does not
+           exist in the chain. *)
+        return_unit
+    | Some predecessor ->
+        let* () = process_head node_ctxt predecessor in
+        let* () = Node_context.save_level node_ctxt head in
+        let* inbox_hash, inbox, inbox_witness, messages, ctxt =
+          Inbox.process_head node_ctxt ~predecessor head
+        in
+        let* () =
+          when_ (Node_context.dal_supported node_ctxt) @@ fun () ->
+          Dal_slots_tracker.process_head node_ctxt head
+        in
+        let* () = process_l1_block_operations ~finalized:false node_ctxt head in
+        (* Avoid storing and publishing commitments if the head is not final. *)
+        (* Avoid triggering the pvm execution if this has been done before for
+           this head. *)
+        let* ctxt, _num_messages, num_ticks, initial_tick =
+          Components.Interpreter.process_head
+            node_ctxt
+            ctxt
+            ~predecessor
+            head
+            (inbox, messages)
+        in
+        let*! context_hash = Context.commit ctxt in
+        let* commitment_hash =
+          Components.Commitment.process_head
+            node_ctxt
+            ~predecessor:predecessor.hash
+            head
+            ctxt
+        in
+        let level = Raw_level.of_int32_exn level in
+        let* previous_commitment_hash =
+          if level = node_ctxt.genesis_info.Sc_rollup.Commitment.level then
+            (* Previous commitment for rollup genesis is itself. *)
+            return node_ctxt.genesis_info.Sc_rollup.Commitment.commitment_hash
+          else
+            let+ pred = Node_context.get_l2_block node_ctxt predecessor.hash in
+            Sc_rollup_block.most_recent_commitment pred.header
+        in
+        let header =
+          Sc_rollup_block.
+            {
+              block_hash = hash;
+              level;
+              predecessor = predecessor.hash;
+              commitment_hash;
+              previous_commitment_hash;
+              context = context_hash;
+              inbox_witness;
+              inbox_hash;
+            }
+        in
+        let l2_block =
+          Sc_rollup_block.{header; content = (); num_ticks; initial_tick}
+        in
+        let* finalized_block, _ =
+          Node_context.nth_predecessor
+            node_ctxt
+            node_ctxt.block_finality_time
+            head
+        in
+        let* () = processed_finalized_block node_ctxt finalized_block in
+        let* () = Node_context.save_l2_head node_ctxt l2_block in
+        let*! () =
+          Daemon_event.new_head_processed hash (Raw_level.to_int32 level)
+        in
+        return_unit
 
   (* [on_layer_1_head node_ctxt head] processes a new head from the L1. It
      also processes any missing blocks that were not processed. Every time a
@@ -393,8 +409,25 @@ module Make (PVM : Pvm.S) = struct
           in
           `Level (Int32.pred origination_level)
     in
-    let* reorg =
-      Layer1.get_tezos_reorg_for_new_head node_ctxt.l1_ctxt old_head head
+    let*! reorg =
+      Node_context.get_tezos_reorg_for_new_head node_ctxt old_head head
+    in
+    let*? reorg =
+      match reorg with
+      | Error trace
+        when TzTrace.fold
+               (fun yes error ->
+                 yes
+                 ||
+                 match error with
+                 | Octez_crawler.Layer_1.Cannot_find_predecessor _ -> true
+                 | _ -> false)
+               false
+               trace ->
+          (* The reorganization could not be computed entirely because of missing
+             info on the Layer 1. We fallback to a recursive process_head. *)
+          Ok {Reorg.no_reorg with new_chain = [head]}
+      | _ -> reorg
     in
     (* TODO: https://gitlab.com/tezos/tezos/-/issues/3348
        Rollback state information on reorganization, i.e. for
diff --git a/src/proto_alpha/lib_sc_rollup_node/dal_slots_tracker.ml b/src/proto_alpha/lib_sc_rollup_node/dal_slots_tracker.ml
index f372fad3e147d99c86ca983f258898e2bed9f0fa..67fcbebfcedfe9efaf5b99b45fc7d539f2f6996f 100644
--- a/src/proto_alpha/lib_sc_rollup_node/dal_slots_tracker.ml
+++ b/src/proto_alpha/lib_sc_rollup_node/dal_slots_tracker.ml
@@ -27,15 +27,15 @@ open Protocol
 open Alpha_context
 module Block_services = Block_services.Make (Protocol) (Protocol)
 
-let ancestor_hash ~number_of_levels {Node_context.genesis_info; l1_ctxt; _} head
-    =
+let ancestor_hash ~number_of_levels
+    ({Node_context.genesis_info; _} as node_ctxt) head =
   let genesis_level = genesis_info.level in
   let rec go number_of_levels (Layer1.{hash; level} as head) =
     let open Lwt_result_syntax in
     if level < Raw_level.to_int32 genesis_level then return_none
     else if number_of_levels = 0 then return_some hash
     else
-      let* pred_head = Layer1.get_predecessor_opt l1_ctxt head in
+      let* pred_head = Node_context.get_predecessor_opt node_ctxt head in
       match pred_head with
       | None -> return_none
       | Some pred_head -> go (number_of_levels - 1) pred_head
@@ -289,8 +289,8 @@ module Confirmed_slots_history = struct
         @@ Dal.Slots_history.History_cache.empty
              ~capacity:(Int64.of_int @@ (num_slots * 60000)))
 
-  let update (Node_context.{l1_ctxt; _} as node_ctxt)
-      Layer1.({hash = head_hash; _} as head) confirmation_info =
+  let update node_ctxt Layer1.({hash = head_hash; _} as head) confirmation_info
+      =
     let open Lwt_result_syntax in
     let* slots_to_save =
       confirmed_slots_with_headers node_ctxt confirmation_info
@@ -302,7 +302,7 @@ module Confirmed_slots_history = struct
           Slot_index.compare a b)
         slots_to_save
     in
-    let* pred = Layer1.get_predecessor l1_ctxt head in
+    let* pred = Node_context.get_predecessor node_ctxt head in
     let* slots_history = slots_history_of_hash node_ctxt pred in
     let* slots_cache = slots_history_cache_of_hash node_ctxt pred in
     let*? slots_history, slots_cache =
diff --git a/src/proto_alpha/lib_sc_rollup_node/inbox.ml b/src/proto_alpha/lib_sc_rollup_node/inbox.ml
index c2415f9f5bbd4ba9477fe8f8c60dba56746c65dd..ae42c820870e13b706e0b1a5db2aa2f553fcc3c9 100644
--- a/src/proto_alpha/lib_sc_rollup_node/inbox.ml
+++ b/src/proto_alpha/lib_sc_rollup_node/inbox.ml
@@ -133,8 +133,8 @@ let add_messages ~is_migration_block ~predecessor_timestamp ~predecessor inbox
          inbox,
          messages_with_protocol_internal_messages )
 
-let process_head (node_ctxt : _ Node_context.t)
-    Layer1.({level; hash = head_hash} as head) =
+let process_head (node_ctxt : _ Node_context.t) ~predecessor
+    Layer1.{level; hash = head_hash} =
   let open Lwt_result_syntax in
   let first_inbox_level =
     Raw_level.to_int32 node_ctxt.genesis_info.level |> Int32.succ
@@ -147,7 +147,6 @@ let process_head (node_ctxt : _ Node_context.t)
           to chain reorganization.
 
     *)
-    let* predecessor = Layer1.get_predecessor node_ctxt.l1_ctxt head in
     let* inbox = Node_context.inbox_of_head node_ctxt predecessor in
     let inbox_metrics = Metrics.Inbox.metrics in
     Prometheus.Gauge.set inbox_metrics.head_inbox_level @@ Int32.to_float level ;
diff --git a/src/proto_alpha/lib_sc_rollup_node/inbox.mli b/src/proto_alpha/lib_sc_rollup_node/inbox.mli
index ecf8e3f83406fea0ad691bd66962303dd5c3cfe8..23c035774f3a6a6824d7a16f456b1ed4d7b4ee8c 100644
--- a/src/proto_alpha/lib_sc_rollup_node/inbox.mli
+++ b/src/proto_alpha/lib_sc_rollup_node/inbox.mli
@@ -36,11 +36,13 @@
 open Protocol.Alpha_context
 open Sc_rollup
 
-(** [process_head node_ctxt head operations] changes the state of the inbox to
-    react to [head]. In particular, this process filters the provided
+(** [process_head node_ctxt ~predecessor head operations] changes the state of
+    the inbox to react to [head] (where [predecessor] is the predecessor of
+    [head] in the L1 chain). In particular, this process filters the provided
     [operations] of the [head] block. *)
 val process_head :
   Node_context.rw ->
+  predecessor:Layer1.head ->
   Layer1.head ->
   (Sc_rollup.Inbox.Hash.t
   * Sc_rollup.Inbox.t
diff --git a/src/proto_alpha/lib_sc_rollup_node/interpreter.ml b/src/proto_alpha/lib_sc_rollup_node/interpreter.ml
index 9a4890a7e852501396f4475f63f3821928010b03..b3f5f911fe2f71b1c16981571af35cada149483a 100644
--- a/src/proto_alpha/lib_sc_rollup_node/interpreter.ml
+++ b/src/proto_alpha/lib_sc_rollup_node/interpreter.ml
@@ -38,6 +38,7 @@ module type S = sig
   val process_head :
     Node_context.rw ->
     'a Context.t ->
+    predecessor:Layer1.head ->
     Layer1.head ->
     Sc_rollup.Inbox.t * Sc_rollup.Inbox_message.t list ->
     ('a Context.t * int * int64 * Sc_rollup.Tick.t) tzresult Lwt.t
@@ -162,16 +163,15 @@ module Make (PVM : Pvm.S) : S with module PVM = PVM = struct
     in
     return (ctxt, num_messages, num_ticks, initial_tick)
 
-  (** [process_head node_ctxt head] runs the PVM for the given head. *)
-  let process_head (node_ctxt : _ Node_context.t) ctxt head inbox_messages =
+  (** [process_head node_ctxt ctxt ~predecessor head] runs the PVM for the given
+      head. *)
+  let process_head (node_ctxt : _ Node_context.t) ctxt ~predecessor head
+      inbox_messages =
     let open Lwt_result_syntax in
     let first_inbox_level =
       Raw_level.to_int32 node_ctxt.genesis_info.level |> Int32.succ
     in
     if head.Layer1.level >= first_inbox_level then
-      let* predecessor =
-        Layer1.get_predecessor node_ctxt.Node_context.l1_ctxt head
-      in
       transition_pvm node_ctxt ctxt predecessor head inbox_messages
     else if head.Layer1.level = Raw_level.to_int32 node_ctxt.genesis_info.level
     then
diff --git a/src/proto_alpha/lib_sc_rollup_node/interpreter.mli b/src/proto_alpha/lib_sc_rollup_node/interpreter.mli
index 18281abb76f28d17fec42853273ca1f28d9aaa93..71cdbcabd249910063015f09d45fc8b4219353f3 100644
--- a/src/proto_alpha/lib_sc_rollup_node/interpreter.mli
+++ b/src/proto_alpha/lib_sc_rollup_node/interpreter.mli
@@ -34,16 +34,18 @@ module type S = sig
   module Free_pvm :
     Fueled_pvm.S with module PVM = PVM and type fuel = Fuel.Free.t
 
-  (** [process_head node_ctxt head (inbox, messages)] interprets the [messages]
-      associated with a [head]. This requires the [inbox] to be updated
-      beforehand. It returns [(ctxt, num_messages, num_ticks, tick)] where
-      [ctxt] is the updated layer 2 context (with the new PVM state),
+  (** [process_head node_ctxt ~predecessor head (inbox, messages)] interprets
+      the [messages] associated with a [head] (where [predecessor] is the
+      predecessor of [head] in the L1 chain). This requires the [inbox] to be
+      updated beforehand. It returns [(ctxt, num_messages, num_ticks, tick)]
+      where [ctxt] is the updated layer 2 context (with the new PVM state),
       [num_messages] is the number of [messages], [num_ticks] is the number of
       ticks taken by the PVM for the evaluation and [tick] is the tick reached
       by the PVM after the evaluation. *)
   val process_head :
     Node_context.rw ->
     'a Context.t ->
+    predecessor:Layer1.head ->
     Layer1.head ->
     Sc_rollup.Inbox.t * Sc_rollup.Inbox_message.t list ->
     ('a Context.t * int * int64 * Sc_rollup.Tick.t) tzresult Lwt.t
diff --git a/src/proto_alpha/lib_sc_rollup_node/layer1.ml b/src/proto_alpha/lib_sc_rollup_node/layer1.ml
index 2bbaf1c0710e05c2ae7cbfec947376bef2438050..d32f5b6d5c3f3d25c5170f6d11526c279a9d6239 100644
--- a/src/proto_alpha/lib_sc_rollup_node/layer1.ml
+++ b/src/proto_alpha/lib_sc_rollup_node/layer1.ml
@@ -78,40 +78,9 @@ let blocks_cache : blocks_cache = Blocks_cache.create 32
 
 include Octez_crawler.Layer_1
 
-let head_of_block_level (hash, level) = {hash; level}
-
-let block_level_of_head {hash; level} = (hash, level)
-
 let iter_heads l1_ctxt f =
   iter_heads l1_ctxt @@ fun (hash, {shell = {level; _}; _}) -> f {hash; level}
 
-let get_predecessor_opt state head =
-  let open Lwt_result_syntax in
-  let+ res = get_predecessor_opt state (block_level_of_head head) in
-  Option.map head_of_block_level res
-
-let get_predecessor state head =
-  let open Lwt_result_syntax in
-  let+ res = get_predecessor state (block_level_of_head head) in
-  head_of_block_level res
-
-let nth_predecessor l1_state n block =
-  let open Lwt_result_syntax in
-  let+ res, preds = nth_predecessor l1_state n (block_level_of_head block) in
-  (head_of_block_level res, List.map head_of_block_level preds)
-
-let get_tezos_reorg_for_new_head l1_ctxt old_head new_head =
-  let open Lwt_result_syntax in
-  let old_head =
-    match old_head with
-    | `Level l -> `Level l
-    | `Head h -> `Head (block_level_of_head h)
-  in
-  let+ reorg =
-    get_tezos_reorg_for_new_head l1_ctxt old_head (block_level_of_head new_head)
-  in
-  Reorg.map head_of_block_level reorg
-
 (**
 
    Helpers
diff --git a/src/proto_alpha/lib_sc_rollup_node/layer1.mli b/src/proto_alpha/lib_sc_rollup_node/layer1.mli
index 1580d1b26f023c61852796180b044bdbc0fbd25f..c9697e4fe5c0eae830ca054d187a4db7489a3f50 100644
--- a/src/proto_alpha/lib_sc_rollup_node/layer1.mli
+++ b/src/proto_alpha/lib_sc_rollup_node/layer1.mli
@@ -47,25 +47,6 @@ val iter_heads : t -> (head -> unit tzresult Lwt.t) -> unit tzresult Lwt.t
 
 (** {2 Helpers } *)
 
-(** [get_predecessor_opt state head] returns the predecessor of block [head],
-    when [head] is not the genesis block. *)
-val get_predecessor_opt : t -> head -> head option tzresult Lwt.t
-
-(** [get_predecessor state head] returns the predecessor block of [head]. *)
-val get_predecessor : t -> head -> head tzresult Lwt.t
-
-(** [nth_predecessor l1_ctxt n head] return [block, history] where [block] is
-    the nth predecessor of [head] and [history] is the list of blocks between
-    [block] (excluded) and [head] (included) on the chain *)
-val nth_predecessor : t -> int -> head -> (head * head list) tzresult Lwt.t
-
-(** [get_tezos_reorg_for_new_head l1_ctxt old_head new_head] returns the
-    reorganization of L1 blocks between [old_head] and [new_head]. If [old_head]
-    is [`Level l], then it returns the reorganization between [new_head] and
-    level [l] on the same chain. *)
-val get_tezos_reorg_for_new_head :
-  t -> [`Head of head | `Level of int32] -> head -> head Reorg.t tzresult Lwt.t
-
 (** [fetch_tezos_shell_header cctxt hash] returns the block shell header of
     [hash]. Looks for the block in the blocks cache first, and fetches it from
     the L1 node otherwise. *)
diff --git a/src/proto_alpha/lib_sc_rollup_node/node_context.ml b/src/proto_alpha/lib_sc_rollup_node/node_context.ml
index 5827936498c5d0195035787925fd0567a4d070f5..93b1838964d106b0780d765fa60b7f8f8d3636b5 100644
--- a/src/proto_alpha/lib_sc_rollup_node/node_context.ml
+++ b/src/proto_alpha/lib_sc_rollup_node/node_context.ml
@@ -1,7 +1,8 @@
 (*****************************************************************************)
 (*                                                                           *)
 (* Open Source License                                                       *)
-(* Copyright (c) 2022 TriliTech <contact@trili.tech>                         *)
+(* Copyright (c) 2023 TriliTech <contact@trili.tech>                         *)
+(* Copyright (c) 2023 Functori, <contact@functori.com>                       *)
 (*                                                                           *)
 (* Permission is hereby granted, free of charge, to any person obtaining a   *)
 (* copy of this software and associated documentation files (the "Software"),*)
@@ -330,6 +331,72 @@ let find_l2_block_by_level node_ctxt level =
   | None -> return_none
   | Some block_hash -> find_l2_block node_ctxt block_hash
 
+let head_of_block_level (hash, level) = {Layer1.hash; level}
+
+let block_level_of_head Layer1.{hash; level} = (hash, level)
+
+let get_l2_block_predecessor node_ctxt hash =
+  let open Lwt_result_syntax in
+  let+ header = Store.L2_blocks.header node_ctxt.store.l2_blocks hash in
+  Option.map
+    (fun {Sc_rollup_block.predecessor; level; _} ->
+      (predecessor, Int32.pred (Raw_level.to_int32 level)))
+    header
+
+let get_predecessor_opt node_ctxt (hash, level) =
+  let open Lwt_result_syntax in
+  let* pred = get_l2_block_predecessor node_ctxt hash in
+  match pred with
+  | Some p -> return_some p
+  | None ->
+      (* [head] is not already known in the L2 chain *)
+      Layer1.get_predecessor_opt node_ctxt.l1_ctxt (hash, level)
+
+let get_predecessor node_ctxt (hash, level) =
+  let open Lwt_result_syntax in
+  let* pred = get_l2_block_predecessor node_ctxt hash in
+  match pred with
+  | Some p -> return p
+  | None ->
+      (* [head] is not already known in the L2 chain *)
+      Layer1.get_predecessor node_ctxt.l1_ctxt (hash, level)
+
+let nth_predecessor node_ctxt n block =
+  let open Lwt_result_syntax in
+  let+ res, preds =
+    Layer1.nth_predecessor
+      ~get_predecessor:(get_predecessor node_ctxt)
+      n
+      (block_level_of_head block)
+  in
+  (head_of_block_level res, List.map head_of_block_level preds)
+
+let get_tezos_reorg_for_new_head node_ctxt old_head new_head =
+  let open Lwt_result_syntax in
+  let old_head =
+    match old_head with
+    | `Level l -> `Level l
+    | `Head h -> `Head (block_level_of_head h)
+  in
+  let+ reorg =
+    Layer1.get_tezos_reorg_for_new_head
+      node_ctxt.l1_ctxt
+      ~get_old_predecessor:(get_predecessor node_ctxt)
+      old_head
+      (block_level_of_head new_head)
+  in
+  Reorg.map head_of_block_level reorg
+
+let get_predecessor_opt node_ctxt head =
+  let open Lwt_result_syntax in
+  let+ res = get_predecessor_opt node_ctxt (block_level_of_head head) in
+  Option.map head_of_block_level res
+
+let get_predecessor node_ctxt head =
+  let open Lwt_result_syntax in
+  let+ res = get_predecessor node_ctxt (block_level_of_head head) in
+  head_of_block_level res
+
 (* TODO: https://gitlab.com/tezos/tezos/-/issues/4128
    Unit test the function tick_search. *)
 
diff --git a/src/proto_alpha/lib_sc_rollup_node/node_context.mli b/src/proto_alpha/lib_sc_rollup_node/node_context.mli
index b62ddddfe2b5195c2e708b2472371ccf3176ea1a..20a8070e8bde3f115f54f08f3fddbef18d8ada0d 100644
--- a/src/proto_alpha/lib_sc_rollup_node/node_context.mli
+++ b/src/proto_alpha/lib_sc_rollup_node/node_context.mli
@@ -1,7 +1,8 @@
 (*****************************************************************************)
 (*                                                                           *)
 (* Open Source License                                                       *)
-(* Copyright (c) 2022 TriliTech <contact@trili.tech>                         *)
+(* Copyright (c) 2023 TriliTech <contact@trili.tech>                         *)
+(* Copyright (c) 2023 Functori, <contact@functori.com>                       *)
 (*                                                                           *)
 (* Permission is hereby granted, free of charge, to any person obtaining a   *)
 (* copy of this software and associated documentation files (the "Software"),*)
@@ -194,6 +195,28 @@ val hash_of_level_opt : _ t -> int32 -> Block_hash.t option tzresult Lwt.t
     if it is known by the Tezos Layer 1 node. *)
 val level_of_hash : _ t -> Block_hash.t -> int32 tzresult Lwt.t
 
+(** [get_predecessor_opt state head] returns the predecessor of block [head],
+    when [head] is not the genesis block. *)
+val get_predecessor_opt :
+  _ t -> Layer1.head -> Layer1.head option tzresult Lwt.t
+
+(** [get_predecessor state head] returns the predecessor block of [head]. *)
+val get_predecessor : _ t -> Layer1.head -> Layer1.head tzresult Lwt.t
+
+(** [nth_predecessor n head] return [block, history] where [block] is the nth
+    predecessor of [head] and [history] is the list of blocks between [block]
+    (excluded) and [head] (included) on the chain. *)
+val nth_predecessor :
+  _ t -> int -> Layer1.head -> (Layer1.head * Layer1.head list) tzresult Lwt.t
+
+(** [get_tezos_reorg_for_new_head node_ctxt old_head new_head] returns the L1
+    reorganization between [old_head] and [new_head]. *)
+val get_tezos_reorg_for_new_head :
+  _ t ->
+  [`Head of Layer1.head | `Level of int32] ->
+  Layer1.head ->
+  Layer1.head Reorg.t tzresult Lwt.t
+
 (** [block_with_tick store ~max_level tick] returns [Some b] where [b] is the
     last layer 2 block which contains the [tick] before [max_level]. If no such
     block exists (the tick happened after [max_level], or we are too late), the
diff --git a/tezt/lib_tezos/sc_rollup_node.ml b/tezt/lib_tezos/sc_rollup_node.ml
index 6e374f9adce1a3faf17f3f213706f2efc3729d4d..0639453e58636455260b0ea509dd81c20d2a5c08 100644
--- a/tezt/lib_tezos/sc_rollup_node.ml
+++ b/tezt/lib_tezos/sc_rollup_node.ml
@@ -37,7 +37,7 @@ module Parameters = struct
     rpc_port : int;
     mode : mode;
     dal_node : Dal_node.t option;
-    node : Node.t;
+    mutable node : Node.t;
     mutable pending_ready : unit option Lwt.u list;
     mutable pending_level : (int * int option Lwt.u) list;
     runner : Runner.t option;
@@ -323,3 +323,8 @@ let run node arguments =
   let* () = run node arguments in
   let* () = wait_for_ready node in
   return ()
+
+let change_node_and_restart sc_rollup_node node =
+  let* () = terminate sc_rollup_node in
+  sc_rollup_node.persistent_state.node <- node ;
+  run sc_rollup_node []
diff --git a/tezt/lib_tezos/sc_rollup_node.mli b/tezt/lib_tezos/sc_rollup_node.mli
index 8097f5c6b37832813ea1937e5347cfbf59dc49b3..f50f8534ff72d4f837ab966fb951b5ce25bd666d 100644
--- a/tezt/lib_tezos/sc_rollup_node.mli
+++ b/tezt/lib_tezos/sc_rollup_node.mli
@@ -170,3 +170,7 @@ val wait_for_level : ?timeout:float -> t -> int -> int Lwt.t
     returned. [where], if present, should describe the constraint that [filter]
     applies. *)
 val wait_for : ?where:string -> t -> string -> (JSON.t -> 'a option) -> 'a Lwt.t
+
+(** Stops the rollup node and restart it, connected to another Tezos Layer 1
+    node. *)
+val change_node_and_restart : t -> Node.t -> unit Lwt.t
diff --git a/tezt/tests/sc_rollup.ml b/tezt/tests/sc_rollup.ml
index 99f0e860353b746480a1d4298f641073edebb4bc..b0d250ebf561bfa3d1a5702a9420ef16fc3f42e8 100644
--- a/tezt/tests/sc_rollup.ml
+++ b/tezt/tests/sc_rollup.ml
@@ -1629,8 +1629,8 @@ let commitment_stored_robust_to_failures protocol sc_rollup_node
     (Some stored_commitment', "stored in second node") ;
   unit
 
-let commitments_reorgs ~kind _protocol sc_rollup_node sc_rollup_client sc_rollup
-    node client =
+let commitments_reorgs ~switch_l1_node ~kind _protocol sc_rollup_node
+    sc_rollup_client sc_rollup node client =
   (* No messages are published after origination, for
      `sc_rollup_commitment_period_in_blocks - 1` levels. Then a divergence
      occurs:  in the first branch one message is published for
@@ -1710,7 +1710,17 @@ let commitments_reorgs ~kind _protocol sc_rollup_node sc_rollup_client sc_rollup
   in
 
   let* () = divergence () in
-  let* () = trigger_reorg () in
+  let* client, node =
+    if switch_l1_node then (
+      (* Switch the L1 node of a rollup node so that reverted blocks are not *)
+      (* available in the new L1 node. *)
+      Log.info "Changing L1 node for rollup node" ;
+      let* () = Sc_rollup_node.change_node_and_restart sc_rollup_node node' in
+      return (client', node'))
+    else
+      let* () = trigger_reorg () in
+      return (client, node)
+  in
   (* After triggering a reorganisation the node should see that there is a more
      attractive head at level `init_level +
      sc_rollup_commitment_period_in_blocks + block_finality_time - 1`.
@@ -4340,7 +4350,12 @@ let register ~kind ~protocols =
     ~kind ;
   test_commitment_scenario
     ~variant:"handles_chain_reorgs"
-    (commitments_reorgs ~kind)
+    (commitments_reorgs ~kind ~switch_l1_node:false)
+    protocols
+    ~kind ;
+  test_commitment_scenario
+    ~variant:"handles_chain_reorgs_missing_blocks"
+    (commitments_reorgs ~kind ~switch_l1_node:true)
     protocols
     ~kind ;
   test_commitment_scenario