iOS FaceID with MAM policy not working and asking for PIN

Has anyone deployed MAM polices to allow iOS FaceID for access to applications? 

Currently we have this deployed to require a pin to access mobile applications in the MAM policy. With the release of the iPhone X, we allowed FaceID in place of the PIN. 

Our current experience is that after the 15 min Timeout requiring users to re-authenticate to the apps, they must use FaceID AND their PIN. Is there something missing or a bug? Do we need to have fingerprint enabled as well? 

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Quick update here and a few tickets with MS - It appears that this is not the expected behavior and has been escalated. The only way to get FaceID to work currently is to enable fingerprint login with FaceID. 

Ill keep this updated as I get more information.