Spot on HotAir, that may even get worse as DEC's come in as they can't get FO's to free up FO's for command courses. Then there is the whole airbus/737 FO thing, wait until the bus FO's start picking up commands on the bus as they have time on type + the 3000 factored. Interesting times ahead, TRSS FO could end up being an FO for the full 5 years...ouch!
Abracadabdra, they do it based on when you get the 3000 factored hours and 2 consecutive 'above average' sims. You then have to convince your base captain to put you forward, which can be easier said than done, depending on which base you are at. You then go through an assessment process and sit in the 'pool' waiting to be plucked out for a course.