I think that's easy enough as we would have that now if Pep had been here for 3 years imo. We could have several homegrown players in the current setup without having to drop a single player from the Champs League squad,registered as U21s but we have sent the most mature of them all away instead.
The 'squad' thing is nailed on simple imo, but the stated aim from Khaldoon & echoed by Kompany, is to have a core of the first team built from homegrown players & they were talking about 'local' players too.
That's a lot tougher, but I wouldn't back against them doing it in a few years.