Hello,
The book is finally out as of September 23.
I'm not sure I would call it a complete documentation of JLC (that would probably require 2000 pages!) but it should be a fairly thorough discussion of most relevant models between 1925 and 1970. It covers about 50-60 watches in great depth and another 90-100 with a little less depth. Definitely a solid start, let's put it that way, as it will include case references, production dates and figures and repair notes.
Thanks,
Zaf