No such agreement between EK and SIA. Absolute bollocks.
SIA mainline will need no new hires since the interest from locals in working after 62 is overwhelming. The percentage of expats is reducing every year and is now down to about 6%.
SIA Cargo on the other hand is hiring, but only DEC. No expat FO:s. Contract for DEC:s is about 10% better than the FO contract in EK and that's mostly due to the decline in the USD. Same T&C:s in SIA Cargo now as in 2005...
If you are an FO there's absolutely no question where you should go.