I got a new Pixel 6a last week and installed GrapheneOS via webinstaller. All was fine until last night when the phone switched off due to empty battery. Today, after charging and booting the phone, it rebooted itself a few seconds after the screen was locked and repeats this behaviour.
The security feature auto-rebooting is OFF.
It does not reboot when the screen is not locked. It does not make a difference whether I lock the screen manually or let it lock itself. I disabled all battery saving measures, I reset the network, reset the app permissions, did a factory reset, even re-flashed GrapheneOS but the problem persists. It is in a state of soft-bootloop if I don't enter the SIM PIN/PIN, as it will reboot, ask for PIN and if PIN is not provided, the screen locks, and it reboots. If PIN is entered and the screen remains unlocked, all is good, I can freely move about the OS, activate and deactivate dev options, OEM lock/unlock etc...
I find no issue like this described anywhere and I would be glad if someone can help me figuring this out.
It is flashed with bluejay-factory-2022082300.zip