Unexpected PA state refund, incorrect interest/penalty calculation

Typically, the state will include an explanation for the refund of the penalty/interest payments on the notice. These commonly include a recalculation or waiver. 

I had exactly the same situation with my CA State tax. TT calculated that I owed a penalty of $291, which I paid.  2 weeks later I received a check for $291, without any explanation whatsoever - just a check.  Since the numbers match, I can only assume it's a refund of the penalty. 

It would appear TT is making a mistake on State Tax penalties.