Air New Zealand has announced 8 firm orders for 787-10 with 20 on option to replace the 8 777-200ER aircraft. The options could be a combination of 787-9 / 10. Orders are set for 2022 but could be accelerated or delayed due to market demand.
Air New Zealand have switched to GE engines to power the aircraft after the issues with the the RR engines.
Air New Zealand will get the modified 787-9 in design by Boeing which will have a higher MTOW allowing for New York, Brazil routes potentially.
Air New Zealand will have a new product for this aircraft which they are currently working on.
The 777X was to big for consideration though could be bought later with market growth increasing demand. It may also be bought to replace the 77W though that will be awhile away considering there young age.
Source Air NZ