"Warhammer Historical Has Now Closed
We can no longer accept any further orders for our products
We would like to thank our customers who have purchased our publications over the years and hope you will continue to get many more years of gaming enjoyment from them."
So it looks like Games Workshop's ginger haired stepchild has finally been unceremoniously dumped. For something like a decade GW has at times given the impression that it was fully behind WHH but for most of that period it was scarcely interested in what to it was surely a niche market. Palming it off to its' Black Library subsidiary can't have helped.
And so that is probably it for Warhammer Ancient Battles, and possibly their other rule sets. Knowing GW I would predict there will be no second life with another publisher for their core rules, I can't imagine them permitting anyone else to develop WAB; as for rules like Kampfgruppe Normandy, which do not use the Warhammer game engine as a core and are the intellectual property of their authors there may be more hope, but only time will tell.