Jump-seating isn't like it once was...
Worked 135 cargo for many years...
Did lots if jump-seating....
Pre-Sept 11, it was pretty easy...there was always a seat available, and I often would get a cockpit jump-seat....some crews who had been together for a few days would sometimes ASK me to sit on the jump-seat even if a seat in first class was available...just to give them a new person to talk too.
Made lots of contacts, got recommendations...
But alas...it not like that anymore.
Even with a GOOD jump-seat agreement, you are the last one to get a seat in the back, and planes are now mostly full.
The saving-grace here for MOST 135 FREIGHT carriers can jump-seat on the mainline cargo outfits in the scheduled runs. But most did not have ID-90 , ETC benefits, cause usually the carrier must be a feeder ti get those for it employees.