EG25 initialization problems

I have an EG25-G Quectel module in my PinePhone and it behaves strange when it just booted.
If the device booted and the suspend cycle is triggered without any phone call or text received, the modem will after resuming because of a phone call send an URC with VOICE <some data> but also NO CARRIER.

This behavior doesn’t happen if a call or text was received after booting before going into suspend.

pinephone:/home/dylan# echo 'AT+COPS?' | atinout - /dev/EG25.AT -

+COPS: 0,0,"CARRIER CARRIER",2

OK
pinephone:/home/dylan# echo 'AT+CREG?' | atinout - /dev/EG25.AT -

+CREG: 0,1

OK
pinephone:/home/dylan# echo 'AT+CEREG?' | atinout - /dev/EG25.AT -

+CEREG: 0,4

OK

It seems that the EG25 module is not properly initialized?
I tried already different SIM cards.

Hi DylanVanAssche,
Thanks for your query in Quectel forums.
+CEREG: 0,4
EG25-G failed to successfully register the network, it needs to check whether the SIM card network business of the card supplier is normal, whether there are problems such as APN, etc.
thanks.

Different SIM card, checking the APN, etc. does not help.

After waiting ~2min after booting, it works flawlessly.
I think there’s still some initialization going on in the modem, is there a way to check if the modem fully operational?

Even though everything works after ~2mins, the CEREG command still returns 0,4.
Is that a bug in the EG25 firmware?