I had an enlightening email exchange this morning with a blogger whose day job is book publicity. She told me that it's their Standard Operating Procedure to put a book into the KDP Select program before its sequel is released, and to do a giveaway just before that release.
I'd been planning to make the ebook of Twin-Bred free -- on my website and via various online vendors, and in multiple formats -- as soon as the sequel, Reach: a Twin-Bred novel, comes out on May 23rd. But I hadn't considered the advantages of having the Amazon machine pushing the freebie with all its mighty algorithms. I believe I need to pursue those advantages. So a few days before May 23rd, I'll be yanking Twin-Bred from Smashwords, through which it's distributed to the Nook Store, iBookstore, Kobobooks, etc., and putting it in KDP Select. (That's assuming Amazon will let me. I had Twin-Bred in Select once before and withdrew it. I believe one can do so once and be forgiven. Do it twice, rumor has it, and that book is barred thenceforth.)
Which means: if you don't have the ebook of Twin-Bred, and you want the ebook, and you need the .epub or you don't like buying from Amazon, then it's time to head to the non-Amazon ebook vendor of your choice -- before the ebook vanishes beyond the Select event horizon for at least ninety days.