Well the official company line is no recruitment for 1 - 2 years. You would think they would be under stating this (as recruitment is a good thing), so I would expect it to be longer.
There is a surplus of somewhere between 100 - 200 pilots, these LWOP and retirements, with the current state of affairs, deal with this surplus. But yes, if in 12 months time the board changes strategy and Qantas expands again, they will have to recruit as they can't get the LWOP guys back! Seems unlikely to happen though