CGNAT blocking download?

I just learned about iOS 16.6 because my employer blocked my phone from using company apps for not having the update. I have my phone set to do the updates automatically...and when I went in there, I got an error message when the phone tried to check for an update. I turned off wifi, and the phone found the update, but can't download it because it's not on wifi. Turn wifi back on, and no update, I get the error message. I strongly suspect that the root of the issue is that my new ISP doesn't give me an IPv4 address, they use carrier grade network address translation (CGNAT) to cut costs. Annoying, but I am getting a gigabit connection dirt cheap. Anyway, I suspect that this use of CGNAT, probably because it prevents Apple from geolocating me, is the problem. Can anyone confirm or deny that you can only get the updates if you have an IPv4 address? That would be...annoying, I'd have to pay the ISP an extra $20/mo for a static IP!