debian+phosh running on PinePhone

[dukla2000]

...

Trouble:
- mobile data not working, if I activate the switch the call signal goes away too (do I have to give some command at to activate the modem?)
...

It seems to me mobile data stability has regressed significantly. I am virtually unable to get it to work myself now whereas a week or so ago it just worked out of the box from Settings. Now disabling WiFi (which is useful to establish if mobile data is working) means the phone has a tendency to enable Airplane mode - you have to keep checking that is not the case.

Something else I have noticed is that 1 of my SIMs (3 UK) seems to have onboard APN definitions and is more likely to work. The other (Virgin UK) does not so I can define goto.virginmobile.uk as the APN but it seems to be less happy to actually try connect for mobile data.

I am not sure if this is something about power saving on the modem - my display spends a lot more time showing 3G connection (despite the fact I can throw a stone at a 4G mast!) Forcing the network selection to 4G seems to keep the display (top status line) consistently on 4G even when there is no connection!

I struggle to define when and what things went backwards as the SIM I mostly have in my PP does not consistently have any data allowance.

At the moment my best guess is the root cause is disabling WiFi is not handled gracefully: if I enable WiFi the mobile data status seems stable and as expected but of course can not be tested!

Code:

~$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
...
2: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
...
      valid_lft forever preferred_lft forever
3: wwan0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 1000
   link/none
   inet 10.101.207.56/28 brd 10.101.207.63 scope global noprefixroute wwan0
      valid_lft forever preferred_lft forever

PS - it seems if I start with WiFi enabled, setup mobile data, then disable WiFi, mobile data works fine until I reboot.