Hi, I don't own this jam just trying to help, but I think you can start tomorrow you'll just be a day behind. Hope that helps
Mark
Viewing post in If I didn't Start Today can I start My week tomorrow? On 25th?
you start late, some people are forced to end early. (I believe some people only have this weekend) It happens. Just do your best and have fun :)
And if you start stressing out because you think you can't finish it: Don't worry, no one manages to finish the game. Just take a deep breath, and see what features you can drop and what bugs you actually need to fix.