Comment by toast0

> Are there ways to prevent this kind of thing using GrapheneOS or FLX1s?

Prevent what exactly?

> If you are on a phone using a network vanilla provider like tmobile or otherwise, is there any way to prevent your phone from trying to connect to a fake network?

LTE and beyond have mutual authentication. Your phone will attach to any network for an emergency call, but attachment to LTE requires the network trusts your sim and your sim trusts the network. [1] No trust on first use necessary, because the SIM includes its private keys and public keys for the network.

[1] https://www.sharetechnote.com/html/Handbook_LTE_Authenticati...