It doesn't apply to GrapheneOS.

Google's upcoming change means Google Mobile Services operating systems will show a warning for apps from unverified developers. Bypassing the warning will require a one-time 24 hour wait via the regular user interface. It can be immediately bypassed using Android Debug Bridge instead.

Developers with Play Store apps are already verified. It's counterproductive for app developers with existing Play Console accounts considered verified to refuse to register their apps distributed outside of the Play Store. That would encourage users to stick to the Play Store.

The problem is for developers without a Play Console account who would need to register and verify their identify to avoid their apps showing a warning. If people are already registered, they might as well list their apps distributed outside the Play Store to avoid the warning.

> Any word as to whether this will apply to GrapheneOS? If I had to choose, I'd block apps that did comply with this BS.

I doubt it, considering Android developer verification will go through Google Play Services, which GrapheneOS has siloed off from most of the OS as far as I'm aware.