I live in NYC and have a Pixel 9 Pro XL running GrapheneOS. I have noticed when I use the phone in the subway that it takes a long time to reconnect when entering stations and sometimes does not connect until I toggle airplane mode. I tried reinstalling Graphene OS several times and nothing changes so I decided to re install again but before locking bootloader I flashed the radios from the official google firmware for my provider (google Fi) and it works perfectly now!.
My questions are: when flashing different radios does it compromise security too much?. also, everytime GrapheneOS updates to a new version, does it update radios erasing the one I manually installed?
Thank you in advance for your comments.