The XML for Analysis request timed out before it was completed

It took 5 hours and then fail in our premium node.

I wouldn't use the word "interesting".  This works as designed.  Semantic Model refreshes on Premium capacities in the Power BI service are terminated after 18000 seconds.

What is "interesting"  is that the same limit is not applied to dataflows (!!!). There you can accrue CU cost way, way beyond that limit.