Clarification on Firebase App Check with Play Integrity and App Distribution

I’ve integrated Firebase App Check into our app using the Play Integrity provider, and it works perfectly when downloading the app from the Play Store’s Internal Testing Track.

However, I’m encountering an issue when using the same AAB through Firebase App Distribution. Specifically, I’m receiving the following error message: 403 body. App attestation failed.

We’ve added the “Internal test certificate” SHA256 and SHA1 values from the Play Store Internal App Sharing page to both the App Check console and the Firebase project settings for the app.

Since Firebase App Distribution uses APKs generated by the Play Store, I was wondering: Is this scenario unsupported by App Check when using the Play Integrity provider? Or am I possibly missing some configuration steps?

I’d appreciate any guidance or insights you can provide to help resolve this issue. Thanks in advance!

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