I had the same experience with 123-reg.
.UK domains added to my list, all of them set to auto-renew. After reading on here about it I decided to leave their status as is up until a week before they were due just to see what would happen. They were never removed from the auto-renew list, 123-reg didn't send out any further communications to customers. No apologies, no corrections, no clarifications. Just a series of automated emails telling me that the .uk domains were due for renewal (and the cost of doing so).
I removed them all from the list myself, I have no problem with registrars offering discounts on new TLDs, that's their line of business and it's fair enough. Auto-assigning a TLD you didn't ask for and then setting it to automatically draw payment is shady though, I've removed all of my .uks and won't be paying for any through 123-reg. If they'd behaved differently I might have grabbed a couple of them.
Only reason I'm still with 123 is because I use them purely as a registrar, and we host everything else...