There’s now a date for the trade paperback of Unknown Kadath, 17th May 2023. Pre-ordering now. It’s just convention that the comics trade calls such things “Book 1” or “Vol. 1”. It’s the complete series of eight ‘spinner-rack comic-books’ (aka ‘floppies’), in one book. It was actually seven, last I heard, so with eight we could be now looking at over 300 pages for the trade paperback including the alternate covers, art gallery, and bonuses. The final part is due as a ‘floppy’ on 26th April 2023, then we get the trade paperback.