Aleksander Morgado authored Dec 16, 2018 and Thomas Haller committed Dec 19, 2018

The 'number' property in GSM settings is a legacy thing that comes
from when ModemManager used user-provided numbers, if any, to connect
3GPP modems.

Since ModemManager 1.0, this property is completely unused for 3GPP
modems, and so it doesn't make sense to use it in the NetworkManager
settings. Ofono does not use it either.

For AT+PPP-based 3GPP modems, the 'number' to call to establish the
data connection is decided by ModemManager itself, e.g. for standard
GSM/UMTS/LTE modems it will connect a given predefined PDP context,
and for other modems like Iridium it will have the number to call
hardcoded in the plugin itself.

https://github.com/NetworkManager/NetworkManager/pull/261