I have written in the ad that the game does not officially start until May 9, and that is still true. However, if you look through the community and user journals, you will see a bit of rping is already going on. So here's what's going on:
Term officially starts May 9--that will be September 1. The days start counting up from there. (I'll post a calendar in the near future that will get stuck at the top of the comm, so everyone can keep track of what day it is.)
For now, it's summer. If you join the game before May 9th, feel free to start rping. Be sure to catch up with the other characters, though!