A new quota system for airlines is being worked on to ensure that New Zealand has enough isolation rooms available at any one time to match the number of people flying back into the country.
It comes as the head of managed isolation and quarantine Air Commodore Darryn Webb says we have almost reached maximum capacity - that is just under 6935 for a two-week period.
"What that means is we provide the airlines with that data so they have a clear understanding of what we have available and then we pass the problem, essentially, over to them to say 'now it's over to you to organise your inbound demand picture to meet our available supply'."
He did not expect there would be an issue with that.
Over a monthly period, the country had managed isolation capacity for just over 12,000 people, he said.
"In the worse case it may mean a slight delay if people can't book a ticket in the very near future, but I am confident that they will still be able to bring New Zealanders."
The length of delay would depend on if there was a surge in demand to return home. Webb estimated it could be a few days or up to a week.
"The voucher system or the ticketing system is the next part of that system, we haven't brought that into effect yet. What we're talking about is a Ministry of Transport-applied rule to the CAA Act where they can advise airlines to place a condition on their air services agreement.
"The ticketing system will follow that. That is essentially where somebody would go to buy a ticket home to New Zealand, they will be redirected to a site which links back to our Covid team and they would need to ensure that they can find a place inside a facility before they can then buy a ticket home."
Asked what that meant for people overseas who had visas expiring and if they might be caught out, Webb said the "key point is that we keep New Zealand safe and that is certainly in front of our thinking and managed isolation really needs to be managed isolation".
There was no current prioritisation for people who had visas running out, he said.
"It will be open to free market flow. So if people want to book the ticket they will go online and to find a place. If it means they want to isolate in a particular location like Christchurch they would be able to find a spot that would take them to Christchurch.
"It may means there is a slight delay and that is regrettable absolutely paramount in our thinking is that we have a managed system that keeps our country safe."
With managed isolation exemptions available again, seven had been issued, primarily on medical grounds, Webb said.
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