That is really weird that it just stops on July 7 and is available on every flight before that (in Y anyway).

Last year, we had no issues getting AKL-RAR and vv on the 777 in J but that was August travel as part of the 32.5k J Asia-Oceania 2 stopover UA award glitch. Seats were there on most AKL-RAR flights at time of booking in March, and more popped up about 2 months before the flights