The prison cookbook from HMP Bargrove is has "It's Not All Porridge and Fresh Meat" printed on the front. "Porridge" was the name of a UK sitcom set in a prison, and fresh meat is a generic term for a new prisoner.
In the actor commentaries on the DVD version, Nick Hancock, one of the actors, refers to the name of this as "Till Death Us Do Part." That was the old traditional wording from the oldest versions of the Church of England Book of Common Prayer. It was amended centuries ago from its former words "death us depart," which had been suitable then because "depart" in that time had the meaning for which "separate" is used now. In more modern decades, the word order in C of E marriage vows was modernized from "death us do part" to "death do us part."
Maya Sondhi has previously appeared in Line of Duty.
Maya Sondhi and Colin McFarlane both appeared previously in Citizen Khan: The In-Laws (2014). McFarlane only appeared in that episode whereas Sondhi was a regular cast member (Shazia Khan).