Hello! It seems I won't be able to finish my game before the deadline, so I'll have to submit only the half-made game :(

Please let me know, when can I upload the full finished game? Is it required to wait any specific time after the Jam deadline before making any updates to the game?

From the FAQ:

• Can I update my game after I’ve submitted it?

Yes! You can update your game after submitting it–even after the jam.