In the 3rd Episode, Peter Kay decided not to use a stunt-voice for the scene where his character was required to sing Elton John's "That's why they call it the Blues". Kay sang the song himself and also did it in his character's voice. However later in the song they did dub in the actual harmonica solo, as Patrick McGuinness could not play the harmonica.
Peter Kay changed the voice of his Character Max for this show. In Phoenix Nights (2001) the character spoke with a much deeper voice. Kay found trying to do this voice for an increased length of time required due to the greater amount of dialogue as the shows star put tremendous strain on his voice, which he then kept losing. He decided to make Max's voice higher than that in Phoenix Nights and decided not to alter his own Bolton accent to protect his voice. At times Max speaks in almost the exact tone of Peter Kay's normal voice, due to how close it now is to his natural voice.
Almost unheard of, this is a spin off series of a spin off series. This is a spin off of Phoenix Nights, which was a spin off of That Peter Kay Thing.
After the mainly off-camera game of 'name the TV theme tune', Paddy states that Billy only correctly identified two TV theme tunes, one of which was 'Porridge'. In fact, 'Porridge' didn't have a "theme tune", it began with a spoken word monologue, and for a time was considered quite unique for being bereft of a 'theme tune'.
Paddy McGuinness has stated in his Autobiography that when he filmed his scenes for Phoenix Nights, he was working at a leisure centre and used holidays and days off to film his scenes. However, for Max and Paddy, he asked if he could take a leave of absence as it required more time, and he was told he couldn't, so he left the leisure centre.