I'm in a similar boat in terms of time sunk. I'm 16 hours in, but not too worried. I know I'll have to crunch, but I'm not currently working.
I'd recommend just getting your game set up so you can play, "win", and restart if you lose (even if it's boring and lame right then because no features). Then add things after that so that you have a nearly submission ready game no matter how far you get! Good luck!