SBD,

just my 2c....

if you are a captain here at nk, why leave to go sit in the right seat for many years.

who knows what will happen with Spirit in the future, or any other airline for that matter....you are in a good place right now....you should hang out and wait to hold cpt in dtw. It will prob take you less time than it would to upgrade at UAL.

Good luck with your decision!!

CS