They made such a huge point of the reveal that there is no way to just back out of it, they would look ridiculous, and be shown as being less than competent.
What they may opt do is just not refer to it again, to just move on and let some time pass, and then slowly reintegrate the status-quo - Timelord from Gallifrey, ran away with Tardis, etc etc.
Of course a snag there is that they annihilated Gallifrey. Annihilated it on the back of Steven Moffat bringing it back from its previous annihilation... and then there is the Ruth-Doctor to clear up.
So on balance there is no easy way to just let it all drop, Chris Chibnall has shown he struggles for original and interesting ideas and has put a good deal of his hopes and plotting into this new mythology, so whatever happens next season we won't be seeing him unwind his own retcon, not in one bound anyway.
Only way this can go would be either admitting that they did a full on COIE and that no prior continuity even exists anymore, or else to have it shown that somehow the Master really was behind all of this and had the DR thinking all of it was true!
This last crappy reveal of the DR to me was as if DC comics decided to now suddenly reveal to us that Superman was never from the Planet Krypton , as that was all a lie, and that he really was an earthling with mutant powers all this time!