Over the next couple of months, all of my eBooks will be coming out of Kindle Unlimited. 
Other authors will be fully aware of the sh*tstorm that is happening with KU right now (which has been going on for some time) readers who don't write & publish may not be aware though.
There is a lot of scamming going on in various ways, some authors are stuffing their books with other books, unrelated content & have even more nefarious ways of adding pages to get more 'reads' per book, bots are adding books with thousands of pages (possibly with one word per page or a bunch of nonsense etc) & then scamming the system by looking as though these books are being read, with bot-driven false page turning.
These bots are then targeting genuine authors that don't game the system, to hide their wrongdoing by 'bot reading' their books. The result is that lots of authors (& I mean lots, not just a few) are having a sudden surge of page reads & Amazon are stripping the reads (which is ok if they're not genuine reads) & are punishing the targeted authors in several ways (not ok).
If an author is targeted, they see a sudden spurt of activity on their page reads but as most (possibly all) of these people are doing promotions, Amazon ads etc, they believe their advertising is working. It's only when Amazon strip their reads & the payment for them, that they complain or read up on this issue in writer's forums etc & learn a whole lot more than they ever believed was possible. Rank is also stripped from the affected authors but that's not even the worst bit... Authors are having their books removed from sale & many are having their accounts closed, after doing nothing wrong.
It's all got very ugly & people are leaving KU in droves.
Some of my books are enrolled in KU until the end of July but some will be coming out soon.
If you're an author & want to know more, a good forum to visit is  Author Support Network (on Facebook).