This was before UA significantly increased flights to New Zealand, but I have booked a number of times directly with NZ. You can make offers to buy up to the next cabin but I have found both coach and their premium economy very good.

UA had lots of upgrade space available this past December and January - far more than i have seen for many years.

I just picked up a G fare to SYD in June at a price I have not seen so low since 2017. I just picked up a super cheap Premium Economy to LHR for Thanksgiving.

Prior to COVID I used to purchase my flights 11 .months out at a really good price but the last couple of years they have been super expensive so it is has been good to see a return to the early discount prices.

I also use Google Flights to track prices. So sometimes the price is not as low as I want so I wait. Other times the price comes down so I change the flight and get a FFC. I fly enough so the FFC makes sense for me.

Enjoy the trip!