Be aware that FedEx has MD-11's in slightly different configurations. I have taken them twice HNL-LAX.
One had two jumpseats in the flight deck and two passenger seats in the cabin.
The other had two jumpseats in the flight deck and two stow-away crew bunks in the cabin which cannot be occupied for takeoff and landing. When I encountered this type of arrangement I got a call from their MEM jumpseat call center telling me I had been "bumped" from the seat I had listed for and would need captain approval to ride upfront. I was a bit confused thinking, "how is this different from any other time I would be asking for a ride from FedEx?" I think what had happened was a tail re-route and jumpseat configurations changed from one type to the other.
Anyhow, most people seem to think that once you list on FedEx, you are golden unless a deadheading crew shows up. Not true. Ground agents in HNL told me that occasionally they will encounter CA's that don't like to have jumpseaters riding upfront with them on longer flights as it gets "too stuffy".