I think ALOT of it will be wrapped up by Bowl season 2021 (at least in terms of most of who is going where)... but I think there will be some pressure to NOT announce all those things officially until at least the Semi-Finals and probably after the NatChamp game.
DATES will still be fluid for a while ... I think the FIRST round will say "Texas and Oklahoma will go to the SEC after the GOR is expired"... and that then sometime in 2022 it will be worked out to let them go earlier for a bunch of face saving reasons....