Who, in their right mind, would leave a regional at most likely captain pay, to go back to $44/hr at a 60 hour guarantee during training, while paying to stay at a crashpad or a hotel. Then on top of that, sit reserve!
If you're going to Virgin/Spirit/JetBlue/Allegiant to go get a type rating to be more marketable to the majors, you've got some serious issues. Unless you maybe enjoy 121 training, along with the stress involved of type rides.