Captains will start to leave easy but it will sadly only be a trickle as it is not as "easy" to find a direct entry command these days. there will be the odd few that are prepared or are indeed young enough to accept a move to the right hand seat in order to move on.
F/o's leaving will be playing onto the hands of management as they will be replaced by TRSS guys that are waiting to be taken on. Sorry to the guys that have chosen this route but TRSS is the cancer of the aviation industry and should be stamped out at all costs!
No other proffesion pays so much in order to get what is essentially an average job so why do pilots insist on doing this!