There is a TOS, printed right in the legal section.
I've never been to their forum, don't plan on going to their forum, and don't really think that it matters what they say in their forum.
Legal page is (or at least almost positively would be considered) the LEGAL terms of use. Until they change their license, it doesn't matter what they talk in a forum.

Also, can they distribute something under 'free to use for any purpose' (paraphrased) and then later recind that, and make it retroactive?
I wouldn't think so. They might get away with it; but written contracts (documented licenses) are not retroactive. You agree to the current terms of use; that's it. Contracts can't be changed by one party; it requires that both parties agree to the changes.
Seems like it would be opening themselves up for legal counter-suits (misrepresentation) if they tried to say that anybody that downloaded and agreed to the terms of the current license would then be liable for a future change to the agreement.

Friends don't let friends use booleans.