Hi ChitlinsCC,
Apologies for this late reply, I've just had some things to do! Just to quickly answer your questions, yes, it almost certainly started after the upgrade to iOS 9, as iOS 8 prior to that had been perfect (in this regard anyway)! It happens with all keys, and in fact can happen in any "direction", so yes, it varies! 🙂 (Interestingly, it can involve punctuation keys too, so pressing 'm' might insert a comma or space character). Also as an example, typing an 'i' might result in a 'u', 'k' or 'o'.
Also, about what the suggestion bar does when (for instance) the system recognises "thanks" as "yhanks", it seems to vary from time to time... sometimes it will correctly suggest "thanks", but at other times, only the left part of the quicktype suggestion bar will be active, just saying "yhanks" in double-quotes. Also, as Bob had suggested, I had indeed tried with all keyboard settings disabled, but, although this problem may have happened a bit less then, it did still occur.
I am just about to try reset settings to see if this makes a difference to the situation, but I apologise that some of my responses to what you'd asked had been a bit brief, because I've had to fight against the iPad a heck of a lot to send this reply, which has made the writing process really difficult (so I had to abandon previous drafts)! So I apologise for that, but thanks anyway for taking an interest and for your questions (hope my answers have been sufficient)!