His tone does frustrate me, but also the few times I have asked to drop a last turn of a trip (captain), he has (begrudgingly) agreed.

I will say, and YMMV, but having worked at another regional (L-XJT), I think our CS are way more professional, understanding, and tend to give us the benefit of the doubt. They operate in the same confines that we are forced to, but I also feel they try to help where they can.