Yes you will need a passport if you want to be in CASS.
Jumpseat privileges should start right away with your carrier and as soon as you can be put in CASS with all the other airlines you have jumpseat agreements with. Remember just because MESA has jumpseat agreements with other airlines, make sure it includes dispatchers.
Somethings you should know about residency. You can keep TX as your legal residence. But you will be earning your paycheck in AZ, thus they will take out AZ state tax and you will have to file as an AZ non-resident at the end of the year. Also MESA may offer medical/dental but you might end up paying more if you keep your family (presuming you are married) in TX. The medical/dental options are based on where you work not were you decide you want to live.
Commuting does suck. Normally it is about a 2.5 hour commute (flight) for me. I have had to fly as much as 5 hours in one day to make it to work on time. Ended up having to fly IND-PHX-DEN because of, take your pick, mechanical, weather issues. Also until you are able to hold a line, you are probably going to be on a relief line. Meaning you won't have a set work schedule and that even makes it harder to commute.
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