I was recently told by a very good source that the time to upgrade from S/O - F/O will be in the 6-8yr range when D-F/O Pax recruitment starts. I would honestly think twice about joining with these prospects. It's not that the S/O job/lifestyle is bad (quite contrary actually) however the real issue is how you perform during your upgrade to F/O 8yrs from now after doing 8yrs of relief work.