Ummmm.....

AI Art by @nightcafestudio

Ummm....

I am not a legal guy, but if Wizards invalidated the OGL 1.0a - all backward agreements - does that invalidate Wizards' protection under the OGL for any content they may have borrowed and put into any 3e, 4e, or 5e books?

If they took anything from a past third-party OGL 1.0a product and printed it in an official book, did they invalidate THEIR protection as well? If they declare the past agreement no longer valid, they don't get to pick and choose. They were just as much a licensee in reverse as those who accepted it were.

Do they have to change books and pull content TOO?

This is potentially massive blowback.