Mugarolla
Light 'em up!
As I said, in my center we are required to talk to either an on car, PDS (who is also an on car) or center manager when we call in "asking" for the day off.
Maybe if you're "asking" for the day off, but if you are "telling" them that you will not be in, an OMS is more than capable of relaying the message to your sup.
Let them try and give you a warning letter because you did not tell your sup personally. The Union will laugh in their face.
If we try to do this through the OMS, primarily because none of the above are available, they will immediately call us back.
So, don't answer the phone. You informed management that you are out of service for the day. That is all that is contractually required.