Does the game have to be pretty polished? I don't know how much time I'll have for pretty game assets but I can get them at least all sketched out.
The game does not have to be polished! The purpose of game jams are to give you a time crunch and motivation to create a game. No one is expected to create the visual novel of the decade, just do the best that you can, because every submitter is a winner 🙌
But I do know of some games that update after the jam period has ended, so if you do, just let the reader know in the game page :)