I found there was availability 330 days out for AKL-LAX and LAX-AKL, so expect you should be booking at about that time. I say "about" because I found NZ's call centre staff to be confuse and the availability seemed patchy - some days you needed to be 330 days out, but then 2 days later they had availability for dates 335+ days out. Just call and keep trying until the dates show up.