Ace Books? Since when? BBC Books has always published North American editions of its books, whether it's the Target reprint, the NSAs or things like Coming of the Terraphiles and Silent Stars Go By. Is this new? Amazon shows a company called Berkeley so has BBC Books lost the rights? Cover art is the same.
Ace Books is part of Berkeley, which is part of Putnam.
For whatever reason, whether the decision was made by BBC Books or by the Douglas Adams estate, the book rights for Shada
in North America were a separate thing. I do know that in the past BBC Books has looked into acquiring a US publisher, but they've never had any interest. In this case, Shada
can be promoted as a Douglas Adams book, and that would be more enticing to a North American publisher than a Dan Abnett book.
What I can say with certainty is that the North American distributor for BBC Books' Doctor Who
product cannot distribute the BBC Books edition of Shada
I'm getting both editions, the UK and the US editions, because if the past is any guide where Douglas Adams books are concerned, they'll differ textually.