Why is that? Not enough upgrading FO's? Also are the chances pretty high of getting the Ejet in training?

Reserve while commuting is a special kind of hell.

All of their advertising says you get to pick your airframe probably why they have to pay extra for people to go CRJ. I haven’t flown with any FOs saying Mesa picked for them.

2 years + on property before you are off reserve as a Ca. Ejet and Crj. Fairly consistent. Some don’t like reserve. Some don’t mind. Commuting on reserve can be bad depending on the commute. It’s not globally bad. Also some say you can’t pickup the 2 and 300 pct on reserve. That’s not true either if you bid a proper schedule.

Does someone ask a poor person how to become rich?
Does someone ask a person who's been divorced, the secret to a good marriage?
The worst thing you can do is ask a fellow regional pilot what move to make. They know nothing outside the regional world.

Being a new F.O on reserve far away from home sucks,your sign bonus will go away quickly.No funny that you have to pay for hotel/crash pad while sitting on reserve.Despite no chances to pickup extra time in your days off. You will ended up flying about +500 a year hoping upgrade to CA in 2 years.Holding a line is a different story. You can make changes in your schedule that will fit in your budget.Seniority is all about it.

Why can’t you pick up open time on your days off? You can bid days off on reserve. Where’s that 500 a year come from? Not at Mesa.

Yes you can, but with not QOL,unless you dont care to work on your days off. +500 hrs /year assuming you are a new hire on reserve commuting to base. If a different story when you hold a line.