After a bit more research, we opted for Consumer Cellular to stay with the AT&T network. There is a $50 incentive we took advantage of (SAVE50), a referral piece from a MIL and the AARP discount.
Transfer was mostly easy, although I had to wait on hold at AT&T for 20 minutes to get some kind of ‘fraud lock’ taken off the account. (Evidently, it prevents someone from hijacking a phone number)
BTW, I had to make five calls to CC as we figured out AT&T’s issues and in each time, I spoke with a rep in seconds…no waits!