The bonuses at the regionals will likely be going away in the next 6 months. The legacies are already slowing hiring with age 67, the slowing of airplane deliveries (Boeing sucks), and a backlog of new hires from 2023. Combine that with the 1500 hour rule likely getting dropped to 1000 hours, there will be plenty of applicants for the regionals.

Jumping to a regional now and taking the huge bonus while they are still offered, and applying like crazy to the legacies might be a really intelligent move. If the legacies don't work out, you still have the regional bonuses and good pay for a while. If you do get called to a legacy, then just pay that bonus back.

Spirit will probably not be around too much longer.