- Edited
Forget about the connectivity checks, WiFi Calling also completely bypasses the VPN. Even if you turn it off, it still resolves the domains which could be used to fingerprint devices on a WiFi network. There is currently no way to prevent this, though the issue has been brought up: https://github.com/GrapheneOS/os-issue-tracker/issues/887
Also, the network assisted location (SUPL) bypasses the vpn, though there is now a toggle for that service.