An off-line pilot can book a (priority 9) UPS domestic jump seat 10 days prior to departure. It's first come, first served, but UPS crew members get to book (priority 7) for personal travel 12 days prior, so we get the first bite at this apple. So, if you book first, and then I try a few days later for my own travel, I don't bump you. However, until the entry door closes, you can always be bumped by a "must ride" (think FAA, check airman doing a check ride, last minute crew out of position).

Once you break the code (find the gateway, get through security, etc.), riding with us should be a pleasure. I really do forward to welcoming off line pilots on my jumpseats ( I have 5 on the MD11), and once you're in our system someone will always show you where to go etc.

Welcome aboard!:)

UPS jumpseating:

They really go out of their way to treat you well, especially in KSDF. UPS pilots are a great bunch. Thanks for all the rides!!!!!!!

As far as jumpseating international. I know the supplementals used to allow it and I think they still do. When I worked for Gemini it wasn't unusual to have an international Jumpseater.
I talked to a buddy at Evergreen and he said they still do it.