They have hired 16 FO's for the NZ operation, I think the majority of those (12) are straight from the Cadet program as CASA and the CAA have signed off on Cadets being based in AKL.
You are right though, since that hiring there have been a number of FO's resign to go to the desert and more will go if Air NZ hire externally again so there will be more recruitment in the next few months.