"De-authorise" doesn't mean anything in the abstract, and I would be very surprised if that phrase appears in v 1.1. (It is not part of the leak that I saw:
We got an official leak of One D&D OGL 1.1! Watch Our Discussion And Reactions!).
If v 1.1 describes v 1.0/1.0a as not an authorised licence agreement, that will have meaning only in the context of the rest of the contract, which will explain the significance of a licence being authorised or not authorised.
Trying to guess what terms WotC will actually insist on is commercial speculation, not legal speculation. From the legal point of view, they could do what you suggest, or they could make it a requirement of entering into the new licence that a party cease to distribue any work licensed under the current OGL. I don't see that either would pose any legal problem.