If we get Z-Forms in October then we likely won't get the starter2's until very late October or Early November. I could see the early October reveal being more exclusive Z-Moves with hints towards Z-Forms.If this:
Aug - Z-Moves
Sep - Exclusive Z-Moves
Oct - Z-Forms
Then:
Nov - ??? (I hope that they reveal a big mystery for us to ponder till the 18th/23rd)