Rls not working on embedded

I'm working with belvoir99 on our product.

We supply the user in the Service via Effective Identity, since we're embedding our report into our website for the "apps owns data" / "embed for your customers" style experience.

We haven't made any changes to the token generation code, which came from Microsoft sample code since 2018; if the APIs have changed could this be a problem?

Another thing to consider; we have one "role" and we decide dynamically what affect that role has on our data based on who the user is via a "user -> organisation" mapping table thus:

[SchoolID] IN

SELECTCOLUMNS(

FILTER(SchoolUser,

SchoolUser[UserSchoolDashboard_Id]=

USERNAME()),

"SchoolID",

[SchoolID])

I have an active support ticket to help resolve this now, just posting this for information to others in case it's useful, or in case they find out why the behaviour has now changed.