I sent the final versions of the proof and index off to my copy editor at Facet earlier this week, so hoping that the book will be published sometime in December.
If you’re thinking of buying a copy, CILIP members are best to order through Facet as you get a substantial discount.
The Handbook is also available in the USA via Neal-Schuman Publishers (there are many examples and readings relevant to US readers and most of the content applies to Special Collections wherever they are).