iPhone upgrade program - account not supported on apple.com

Just to respond to my own message in case somebody has a similar problem. I spoke to Verizon first, and there's nothing wrong with my account. It's a personal account, not prepaid, not business, it's completely fine. I then was on the phone with Apple for an hour. While the person I spoke to was super nice, they had no idea, they couldn't escalate, they couldn't report this as a bug, and couldn't tell me who else to talk to. Since nobody I can actually speak to has any clue what's going on, I'm going to just leave the upgrade program, either this year or next when it's up, and start buying phones again by paying up front. That seems to be the only solution since if you buy a phone outright it doesn't ask for a carrier check if you choose SIM-free phone.

Obviously somebody somewhere knows what's going on, but I have no way to reach that person.

Same, my first time with Verizon too. Thought it was something with my account. Interesting that you got that statement from them; nobody I talked to had any clue. No issues in the past with AT&T ever. However I will say, that it's nice to have full cell coverage at my house when AT&T gave us 0-1 bars, and even when it "thought" it had a connection and would drop me off wifi calling, it didn't. So I'll take better reception at this point, even though I'm frustrated. I'm still going to pull out of the program though I think. We figured it out and with trade in it's about the same, just one way you're paying up front.