Can I change the firmware with regional restrictions?

[YourNesquik]

Hello! Can you please tell me, I'm expecting a package of Pinephone. Tentatively, it will have firmware EG25GGBR07A08M2G_30.200.30.200 or higher. Such firmware, according to the documentation, has a new network function. It is related to blocking the modem operation in some regions of the world. Do I understand correctly that the custom firmware allows to remove this limitation?

P.S. I have explored youtube, but nowhere could I find video instructions on how to use “pinephone modem sdk” for PinePhone. Maybe you have a link?