[QUOTE=RBZL;2264654]Yes, immediately.
Not at all bases....they are holding some FOs to seat lock policy. Not always, but it does happen. If the base doesn't need captains (maybe they hired to many street captains), they won't waive the seat lock.
I know one FO in DEN who has 1600 hrs and a year at the company. Wanted to upgrade....Nope, seat locked. Now he's in the right seat with captains who have both less TT and less seniority. That's an exception to the norm, but keep in mind you're not guaranteed an upgrade at 135 PIC mins.