He forgot you are pretty much "hot reserve" all day everyday.
As a line holder they can still do whatever they want with you as long as you are back in base within 2 hrs of your original release time.
If you have a sit in your schedule more then 2 hrs they blow up your phone and try to reassign you.
All captains are duel qualified so they fly CA/CA everyday.
They will reassign you as a CA to fly right seat to a Jr CA or even fly right seat to a management pilot that was hired just as a sim instructor.
Only DEN Q pilots are ASE qualified and as a DEN CA if you fly an ASE turn you get 200% pay not just for overtime but 200% for your "BID AWARDED" ASE turn.