Much of these cancellations have been flowing on for quite some time.

We were booked on NZ23 YVR-AKL on 25 Oct. Woke that morning in Vancouver to an email from NZ saying the flight was cancelled due to 'engineering' issues. It took us two and a half hours on the phone to sort out. I ran out of my roaming allowance.

NZ accommodated us on UA to LAX then NZ3 to AKL one day later.

There are some consequences for NZ - as well as reimbursing us for meals and accommodation the Canadian Transport Agency mandates $1000 CAD per passenger for delays that are over 9 hours. Will be interesting to see whether NZ pay up at first time of asking.

From the CTA website, and this applies to all flights to or from Canada.

"Compensation

Airlines should give passengers as much notice as possible that their flight will be delayed or cancelled. If an airline informs the passengers 14 days or less before their original departure time, they will have to compensate the passengers for the inconvenience of the disruption. The amount of compensation depends on how late the passenger arrives at their destination, compared to the arrival time indicated on their original ticket.

Large airlines must pay:

• $400 if the passenger arrives three or more hours late, but less than six hours;
• $700 if the passenger arrives six or more hours late, but less than nine hours; and
• $1,000 if the passenger arrives nine or more hours late."

<Source: https://otc-cta.gc.ca/eng/publication/flight-delays-and-cancellations-a-guide>

I won't hold my breath as to whether the NZ government (the majority shareholder in NZ) regulate/legislate in a similar way.