If you are among the few with a modifiable module, here are the general steps that "work" for some: 1. Standard AT Command Method
The main hurdle for the L850-GL is a security feature called . fibocom l850gl change imei work
Most L850-GL modules come with a high security level that prevents the standard AT+EGMR commands from working. If you are among the few with a
Настройка поддержки модема Fibocom 850/860 в OpenWRT fibocom l850gl change imei work
Some versions require you to first disable write protection with AT+EGMR=0,1 before setting the new number. 2. Specialized Scripting (OpenWRT)