Olivia Cooke (Emma) stated in a recent interview that as being executive producer of the film, it meant she could use her own native accent for the role for the first time since she was 18, due to her control over the film and her character.
The whole film was both written and production finished before the COVID-19 pandemic even existed.
Olivia Cooke has stated that her character Emma is, she believes, the closest she has ever been to playing herself.
When Emma (Olivia Cooke) calls her Mum, the image seen on the contact profile is actually Olivia's Mum in real-life, Lindsy Cooke.