When I try to search for how to submit to "Kindle Singles" and their guidelines, etc., the only page I can find through Amazon is the following:
"Submissions Policy
Kindle Singles is not accepting unsolicited manuscripts at this time. Our editors will respond to all submissions currently in the queue as of June 22nd, 2017."
I'm guessing this just means they are not taking submissions at this time because, and I'm only guessing, they want to catch up with submissions made before June 22nd before taking in more?
Read more: Kindle Single Guidelines?