The stress of furiously pressing the upload button and the page not responding surely felt like a nightmare but at the end it was a blessing.
Did you get anything out of the extra hour? Maybe fixing a fatal bug?
In our case we managed to squeeze a cool fading to black effect when the character is dying due to the lack of oxygen.
Check out our game Hypoxia: https://itch.io/jam/gmtk-2019/rate/463127