City will have to submit their List A squad on Friday 1 September 2017 (midnight CET).
What is List A and how does it work?
List A squads are viable from the first match in the group stage up to the final. Clubs are allowed a maximum of 25 players on List A for the season - two of which must be goalkeepers.
Eight places of 25 are held for 'locally trained players' and clubs are allowed a maximum of four 'association trained players' listed as part of the eight.
Some of those who could qualify for the eight locally trained/association trained slots are Kyle Walker, Tosin Adarabioyo, John Stones, Phil Foden, Fabian Delph and Raheem Sterling. It is not a requirement fill all eight spaces.
Can they add other players?
If City are still involved in the competition during knockout stages, Pep Guardiola is allowed to add a maximum of three new eligible players to his squad for the remaining matches. This must be completed by Thursday 1 February 2018 (midnight CET).
Also, the Club may register a maximum of one new eligible player to List A after the deadline, provided the quota of locally trained players is met. This must be completed by midnight CET before the relevant first-leg match.
In addition, players who are born on or after the 1 January 1996 and have played for the club for an uninterrupted period of two years can be registered on another list, known as List B. This is a good way to involve Under-21s and still allow space in List A.