I doubt if this is much help, but if you are going to jumpseat, you will have to be counted as crew, BUT you have to be on the general declaration. This works in both directions. List for the jumpseat early, check in early, check with the agent to make sure you are on the gen dec. Intercept the crew flying out.

I only did it once coming out of one of the carribean islands and it was a bit foreign to the agents and therefore difficult for me. Do not take my word for it, but call the jumpseat desk (if we still have one) and get the whole answer from them.