There is a lot of informaiton about Maxjet on
www.flightattendants.org
I do not think they have direct entry senior positions, I believe it is all based on seniority. Most (if not all) US airlines would not use that process. I would venture a guess that some Americans would be willing to be based in STN and fly senior. Or, if they are like Eos, it is a bid position and you may fly it one trip and not the next.