I don't know if this has been discussed but it seems clear now that Taylor is a flight attendant for American Airlines. She was wearing her uniform scarf in the episode which my rough googling points to AA. Also googling "flight attendant school phoenix" indicates that AA has flight attendant training in phoenix and charlotte (though that is changing since the merge with US airways at the end of last year). I am assuming all the filming was done before the merge. So her possible hub cities include: Dallas, Phoenix, NYC, LA, Miami, Chicago, Philadelphia, Charlotte, or DC. I don't know how competitive each market is. We may have to wait until next episode. Taylor did mention an east coast possibility which doesn't really narrow it down.
All this just makes me think all the RV and job fights were for show. That Taylor and David both knew Taylor would be training to be a flight attendant and that they would have to relocate once she finished. Though I still believe they really stayed at an apartment some place and filmed in the RV for the show. With all of Taylor's "stuff" it's clear she didn't really move into the RV. David crying about his teacher's contract will probably end up being no big deal.