XMLA fail to connect suddenly

[ajr]

Update: Issue seems to be resolved.

XMLA conenction worked last week, now I am getting an error;

MWC token validation failed: Invalid Token type, expected MwcToken but got AadBasedToken

This happens in Power BI Desktop, SSMS, Tabular Editor 2, and DAX Studio. I've tried using my user account and a service account but both fail to connect.

Any help would be appreciated.

Update: I've opened a support ticket, response was; "We are currently investigating this same behavior that seems to be impacting multiple customers. We are already in the process of creating an internal incident for the Product Team and we are also attempting to make it high priority to be worked as soon as possible."