According to my calculations at http://www.elections.org.nz/calculator/index.html (and using these results) this creates a Parliament of 121 seats, and the following blocs of parties:
National + United = 60
Green + Labour + Mana = 50
Maori = 3
New Zealand First = 8
That immediately creates some exciting options for coalitions and re-negotiation of confidence and supply agreements.
It would also take rhetorically take off the table everything that National and ACT agreed to in their confidence and supply agreement.
Is that right? Am I missing anything in my workings-out?
EDITED TO ADD: Graeme Edgeler posts about an even more intricate version of this type of scenario, here. Extrapolating from his post, it seems that ACT would not disappear from Parliament after this result:
[A] policy decision was taken that finality was more important than proportionality, and the possibility that an election petition (or by-election) could change multiple seats (e.g. by removing a party from Parliament because it no longer passed the one seat threshold) months after an election was thought to be the greater evil.