I don't mean to be pessimistic, but we may have to wait until August 1. I went back and looked at the first page of the thread with the historical data.
The summer (peak) months were opened two months out. But February, March, April and May were opened one month out.
That being said, September of 2012 opened on July 3rd.
Of course, I'll be checking every day no matter what logic I use!