Spider Jerusalem

This was years ago - but I feel like the solution for CGNAT at the time required a static, and we also implemented DDNS for their TLD. It definitely wasn’t T-Mobile. It took some time to find someone at the mobile ISP who understood what we needed, and what options existed.

ISP may offer a static IP, and/or help bypassing CGNAT if either are useful. I’ve done it for a 5G failover with VPN, with the gateway in passthru, and a firewall behind it. At a glance, it looks like the FX4100 supports all of this

Policy on the local machine - or in the case of home, registry settings. Granted, the settings app can bug out, but if it’s a consistent problem, it’s the first thing to come to mind. If you can search for windows update settings, but clicking on it leads to something else, that would be consistent with such a change.

Wouldn’t hurt to check group policy.