Air New Zealand is changing flight times for close to 2000 international flights next year which could affect travel plans for hundreds of thousands of passengers, some of whom will have to re-organise their holidays.

While the number of passengers who now have to fly on a different day is relatively low, they face having to re-book accommodation, rental cars and activities at their destination.

In response to questions after a passenger had flights changed next April, Air New Zealand said it was trying to build more flexibility into its network.

 “As we did in August this year, we’ve made some changes to our long-haul schedule between the end of March and October to build flex and certainty into our network,” said Air New Zealand chief customer and sales officer Leanne Geraghty.

She said adjustments had been made to 1900 flights across an eight-month period.

That would “‘give our customers surety that in the event of a disrupt, we have aircraft and crew available to get them where they need to be”.

About 90 per cent of changes are retimed within 60 minutes, or changes to the aircraft type.

But the remaining 10 per cent of flights mean passengers can’t travel on the day they’ve booked. They have been offered flights one day either side of the one they’ve booked.

One Auckland man said he was frustrated at the sudden flight cancellation without any explanation.

The man and his wife have been planning - and saving hard for - a trip to America with their three adult children and their families since before Covid hit. There are nine adults and five children in total so it’s taken a lot of planning and logistics for the once in a lifetime six-week family trip.

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“How can Air New Zealand just cancel a flight four months out without any explanation whatsoever? That costs us as a group.”

Going a day or two later wasn’t an option as all accommodation, many of the activities and a cruise have already been booked and paid for by the group and couldn’t be changed around.

They are now having to leave a day earlier which has increased the costs once food, accommodation and the new flights - an additional $4200 to get similar seats - are factored in.

“It’s cost us $6500 added to our trip - money we now have to try and somehow claw back from parts of the trip. What frustrates me is they didn’t even offer any explanation to the travel agent,’' he said.

Air New Zealand says domestic flights are not affected.

Leanne Geraghty, Air NZ's chief customer and sales officer. Photo / Brett Phibbs

The airline is still struggling to match capacity with still strong demand. That has made finding flights more difficult and sent fares sky-high.

Geraghty said by late May the airline will have all seven of its Boeing 777-300 aircraft flying again.

That would “be an important moment for us as it will help to further ease the capacity constraints we are seeing”.

The airline has retired all of its eight smaller 777-200s which were sent into deep storage early in the pandemic.

The airline was also bringing on another 700 staff by the end of February. It has rehired about 2000 staff during the past 12 months but is still facing some Covid-19 sickness disruption.

House of Travel commercial director Brent Thomas said hotel bookings, cruise holidays and rental car reservations would have to be re-jigged for those now travelling on different days. Those who had booked through agents could contact them to get this done.

He said Air New Zealand had done the right thing.

“This is a lot of work for us but good on them for giving us plenty of warning.”

Thomas said the return of more aircraft is welcome news as there was no sign of any drop off in demand for travel, despite the prospects of a recession next year.

Bookings in the week before Christmas traditionally tapered off but there had been no slowdown this year.

In August the airline cut its summer schedule by 1.5 per cent to build more flexibility into the schedule following disruptions due to illness and staff shortages.

It said then it wanted to avoid short-notice disruption.

To help build more padding into its network over summer it has contracted Spanish wet lease operator Wamos to fly between Auckland and Perth. Wamos provides the plane and crew to operate the service, freeing up Air New Zealand resources to be used on other routes.

The airline is gearing up for its busiest day in nearly three years tomorrow, with more than 55,000 passengers on its network. It is urging patience from those who may face delays or be in queues for longer than usual.