I don't think they will openly propose to release anyone, regardless of the outcome of the appeal. They may end up proposing a scenario where they have some players who are excluded from the the GP squad and only play in Europe, I can't see it being accepted but suspect it will be a move they put forward.
There will be some players who are out of contract at the end of the season, who may be released early if a destination is found, don't know enough about who they might be. ED is an odd one, he hasn't played yet and to be honest I don't think they actually need him, so depending on what he has signed up to then he may find himself caught up in all of this as his contract may be one of the more creative ones, given that he moved for a sandwich and the glory of playing for Saracens ;-)
Liam Williams looks to be heading back to Wales, so he may be released early and Joel Kpoku is rumoured to be heading to Saints ,however his salary will be tiny compared to some of the EA Galacticos and hardly make a dent in the suggested £900k gap.
There does appear to be a lot of moving parts to consider, I am sure the EAs have a plan as they will have known about this for some time, my biggest fear is that they appeal and PRL reduces the points penalty as a soft option and a way of keeping the noise down.