I think a useful way to frame this is looking at Pep's time here, and seeing how big his squad has been, but also, how many in the squad did he actually use.
How many played > 500 minutes (most likely useful players), or how many played between 200 and 500 (passengers but played some minutes, likely not just preseason minutes).
16/17 Season
More than 500 mins (core players): 23 players
200 - 500 mins: 2
17/18 Season (Centurians)
More than 500 mins (core players): 21 players
200 - 500 mins: 4
18/19 Season
More than 500 mins (core players): 21 players
200 - 500 mins: 3
19/20 Season
More than 500 mins (core players): 22 players
200 - 500 mins: 1
20/21 Season
More than 500 mins (core players): 22 players
200 - 500 mins: 1
21/22 Season
More than 500 mins (core players): 20 players
200 - 500 mins: 2
22/23 Season (Treble)
More than 500 mins (core players): 22 players
200 - 500 mins: 0
23/24 Season
More than 500 mins (core players): 20 players
200 - 500 mins: 2 (Gomez and Phillips).
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This shows clearly that Pep has relied on less and less players overall as the years progressed (25, 25, 24, 23, 23, 22, 22, 22) but his core players (relies on), has usually been about 21 or 22.
Our 2 bit part players this season (Gomez and Phillips) are likely gone, while Bobb, Lewis and Nunes will get more minutes next season and stay as core players (likely taking some minutes from Kevin, Bernie as they get older). But this would leave us still with 20 + 0 = 20 players.
I don't think any loanees are coming in, so with Savio making it 21, I think we are guaranteed 1 more player on top of Savio, to have 22 core players. There could be some young project player or academy players join, but they are unlikely to get more than 500 mins.
And that's likely it. If anybody leaves, then obviously there will be a 1 in and 1 out happening. It's in line with the last couple of years on the squad size Pep uses. The only time he actually relied on 23 core players was his 1st season, and that's because of squad bloat and before Pep could make the squad his own.
He clearly relies on around 21 - 22 core players, with a couple of bit part players to pad it out. Maybe this means McAtee stays to get like 300 minutes or something, or some random academy players.