"I did some research about the PTR btw.
An October release is now looking somewhat possible. Each pre-patch since WoD (I didn't look back further) seems to land 4-5 weeks before the pre-patch itself lands, & pre-patch tends to last about 3-4 weeks before the expansion launches. If this follows a similar trend, then October is possible, although I'd still wager November is more likely given how much there is to tune.
8.0 PTR: 14/06
8.0 Release: 17/07
7.0 PTR: 15/06~ (can't find for sure)
7.0 Release: 19/07
6.0 PTR: 11/9
6.0 Release: 14/10"