How to set up a cellular network connection from the command line

I have a cellular modem connected to my board (using a Toradex Apalis on top of Toradex Ixora).
Running LTS 21.6 + Jetpack
I can setup the modem connection from the graphics environment, but sometimes we switch to a different cellular provider so we need to modify the APN.
nmcli in more recent versions supports this type of operation (Creating/modifying a connection), but the version included in LTS doesn’t.
Besides upgrading nmcli (I tried and had some issues), is there another way to update the APN without using the desktop UI?

$nmcli -v
nmcli tool, version
$ nmcli con edit
Usage: nmcli connection { COMMAND | help }
COMMAND := { list | status | up | down | delete }
Error: 'con' command 'edit' is not valid.