It seems EC25-E is not able to bridge between mobile network and usb.
Best case would be that at least ECM protocol could be bridged but RNDIS would be ok for now although Linux mainline kernel plans to drop support for it.
How about adding AT command which dsables modems dhcp clients, dhcp server and maybe other services which depend on those and just bridge mobile interface and usb together?
Does someone know if firmware by default has support for bridges, ip link help or brctl commands might tell me how hard this would be to fix modifying it?
Local network operators offer public ipv6 subnet and as a special service public ipv4 address, by default everything ipv4 is allready NATed on their end and this is not good if public addresses jam into modem.
Do any other of Quectel 4G/5G modems offer this kind of functionality?