Trust me mate, terms and conditions are far far more important than progression. FO / CAPTAIN for a sh*t airline or SO / FO for Air New Zealand. I think that I would sit fat dumb and happy as an SO, you would be taking a pay cut to go to Jetstar as an FO, would be a minimum of 3 years to command and by then the expansion may have stopped and you might end up stuck as an FO at Jetstar