Well, here is the full list of November releases, and I don't see any Tempestus Firebases on it. Perhaps it is going to be a December bundle deal, or the rumor is bust. Hard to say at the moment.
In the meantime, you can see the pricing for your 2nd wave of Dark Elves, Triumph and Treachery, and more. Of course the biggest bit for me is that the Black Legion will get its hardcover version towards the later end of the month. Exciting!!!!!