We would consider such a game to be longer than 20 seconds. It’s not what we’re looking for but it wouldn’t get your game disqualified either.
The games that we’re disqualifying are entries that have nothing whatsoever to do with 20 seconds of time where it’s very questionable they were even made for our jam.
So you’ll be fine with that design if it what you really want to do, but we’d suggest exploring other ways to differentiate across playthroughs