Mmmmm ......
I'd hate to be accused of being cynical ... BUT perhaps they're hireing only US nationals so they will have no arguments about flying around the Saudi skys at night at 500' agl and complying with FAA Part 91 duty rules .... which might also be why they will try (?) to do the 28-28 on/off thing as well.
Anyway good luck to all the 'lucky' aviators who get the gig!
You'll really enjoy yourselves ......