The new preview feature of dynamic format strings for measures only appears to work if the measure is created within the Power BI dataset.
It will not work if I create a measure in a report which is live connected to a Power BI dataset.
It will therefore also not work if I create a measure in a report which is live connect to an AAS model.
I would like to know if:
a) this is a known issue
b) there is a plan to enable this in reports, not just datasets, so that dynamic format strings can be set on measures stored in the report rather than the data model