@xginn8 @imrehg - I followed the suggestions above. On initial installation of Raspbian (standard), I had both wireless and LAN connectivity. Once I did the “apt update” and “apt full upgrade”, I lost both of those connections, and was unable to install modemmanager (although Raspbian did recognize that there was a modem in place, and had an IP for it). A reboot fixed the ETH0 conenction, so I was able to continue somewhat. This is already noted here: https://forums.balena.io/t/connect-to-wifi/4543
Reflashing with Raspbian (standard), and attempting to install modemmanager results in a number of errors, mostly because the latest version of modemmanager requires some of the updates noted above. I am able to bring up the modem, but I can’t see the SIM card at all (“unknown”).
The update issue is a real problem right now. I am going to try again with Raspbian Lite, and go pure command line. Hopefully the updates there will not lose the networking connections.
More to follow.
John