I think keeping a legacy (jam-version) file is what's best if you want to keep pushing updates while keeping it fair since this is what the hosts had to say about it: "We request you maintain a 7DRL version of your game for reference. People judging may elect to play either that one or the latest. Change notes can specify what was fixed / added so the judges can take that into account even if they play the latest version.
You can direct people to the latest & best version, however, as we'd want the normal players of your game to have the best experience as possible."