Leading health experts have set out how New Zealand's Covid-19 alert levels could be revised, with a seven-tier system designed to better manage local outbreaks.
When Auckland dropped down to level 2 today, apprehensive Otago University epidemiologists thought the safer move might have been a shift instead to level "2.5".
Now, they've suggested overhauling the four-step system into a wider, tidier and more sophisticated one they say could see the country through the rest of the Covid-19 crisis.
But Covid-19 Response Minister Chris Hipkins tonight signalled little appetite for a revamp to the current system.
Professor Michael Baker said it had proved "excellent" and fit for purpose when it was rolled out amid last year's main outbreak.
"It was really designed for a situation where the emphasis was on lockdown - and the stay-at-home orders, which acted as a circuit-breaker, was a very effective way of eliminating the virus."
Since then, however, several key things had changed.
"It's now being used in a much more targeted way to support something that we didn't have a year ago - that's a highly developed contact tracing system."
And as the latest episode showed, the system was also being used at local levels to implement regional lockdowns and travel restrictions.
"The third thing that's changed is we now know much more about how the virus is transmitted," he said.
"The most effective measure for limiting spread, other than physical distancing or staying at home, is mask use - yet that's never been integrated into it very well, and is more just a bit of an add on."
A case in point was a fresh tweak that just extended Auckland's requirements to mask use on public transport at all levels, to the rest of New Zealand.
"This just shows the system is no longer fit for purpose, and it's meant that officials have had to make ad hoc restrictions in some places but not others," he said.
"We think it's time to revise it: do it once, do it properly, and let's get something that'll see us through to the end of the pandemic.
"It may even provide a legacy tool for the future."
When it came to the current settings, Baker saw particular problems with level 2.
"It pretty much means nothing to a lot of people - and they revert to business as usual behaviour."
The system that he and fellow epidemiologists Professor Nick Wilson and Dr Amanda Kvalsvig favoured could offer a smarter solution, with slight but clearer differences between each level.
NZ's re-imagined system
Alert level "0" would essentially be a pre-pandemic state, with no restrictions in New Zealand or at borders.
A new alert level "1" came with restrictions at borders only, while level "2" required masks on all public transport, domestic flights, aged residential care facilities.
There would be no restrictions on gatherings, although contact details of anyone attending events larger than 100 people would need to be collected.
Gatherings under level 3 would be capped to 20 people - or 50 for funerals - with no travel from any designated outbreak region to the other major island within New Zealand, save for emergency vehicles.
At alert level 4, masks would become compulsory in all indoor settings - such as workplaces, secondary schools, shops, social settings and transport, but voluntary in primary schools and homes.
Travel outside any designated outbreak region, except for in medical emergencies, would be prohibited, while social gatherings, including funerals, would be limited to 10.
Under level 5, people would be required to stay within their bubbles when not at work or at school, but these could be expanded to bring in caregivers, or to support isolated people.
Again, masks would be required in all indoor spaces, as would physical distancing - two metres in public and in stores like supermarkets, and one metre in workplaces and schools.
Travel within local areas would be permitted - but only for going to work, school, shopping or getting exercise - and gatherings of up to 10 people would be allowed only for wedding services and funerals.
Any places at high risk of fostering "super-spreader" events - such as cafes, restaurants, pubs, nightclubs, gyms and churches - would close.
Under alert level 6 - the most stringent level - people would have to stay in their bubble other than for essential personal movement, although safe recreational activity would still be allowed in local areas.
Face masks would be required in all indoor public settings, travel would be severely limited, all public venues and schools would be closed, and all gatherings cancelled.
As with the current level 4, the only businesses allowed to stay open would be essential services like supermarkets, pharmacies, health clinics and petrol stations.
"Essentially, the upper two levels would be stay at home orders, which leaves three other levels relating to varying degrees of concern about heightened risk," Baker said.
"In an instance like the Northland cases, people in that region would move from level 1 to level 2, which would just require a bit more vigilance," he said.
"If concern grew further, the levels could move up once more, meaning restrictions around mask use in indoor environments, and on gathering sizes.
"A big part of it is simply trying to avoid those stay-at-home orders, which are much tougher on people and on the economy."
Tonight, Hipkins told the Herald the Government operated under a "continual system of improvement" - and that included ensuring the alert level system was fit for purpose.
"We have used variations to the alert levels or interim steps in the past to fit the situations we have been faced with - for example the use of alert level 2.5 in Auckland during August, and the current requirement that face coverings are used on public transport at alert level 1."
He added the Government had always indicated the system could be applied regionally, as it had done for the Auckland region this week, and in August.
"As it stands the alert level system has and continues to serve the country well, as we all understand what each level means for us."
The Seven Levels
ALERT LEVEL 0: No Covid-19 restrictions within New Zealand or at borders
ALERT LEVEL 1: No restrictions in New Zealand but entry at borders is restricted
ALERT LEVEL 2: Masks required on all public transport, domestic flights, aged residential care facilities, and must be worn by taxi and ride-share drivers. No restrictions on gatherings, but contact details of attendees must be collected for events larger than 100 people.
ALERT LEVEL 3: Masks required in all public transport, domestic flights, health care settings, and aged residential care facilities, and must be worn by taxi and rideshare drivers. No travel from any designated outbreak region to the other major island within New Zealand (with exemptions for emergency vehicles only). All social gatherings limited to 20 people, or 50 for funerals and tangihanga.
ALERT LEVEL 4: Masks required in all indoor public settings, such as workplaces, secondary schools, shops, social settings and transport, but voluntary in primary schools and homes. No travel permitted outside any designated outbreak region, excepting medical emergencies. All social gatherings limited to 10 people, including funerals and tangihanga.
ALERT LEVEL 5: Masks required in all indoor public settings, voluntary in homes. Requirement to stay within your household bubble whenever you're not at work or school. The bubble may be expanded to connect with close family and whānau, to bring in caregivers, or support isolated people. Physical distancing required when in public and retail stores (two metres) and in workplaces and schools (one metre). Travel within your local area permitted for going to work or school, shopping, or getting exercise. Gatherings of up to 10 people can continue, but only for wedding services, funerals and tangihanga. All settings at high risk for super-spreading events are closed.
ALERT LEVEL 6: Masks required in all indoor public settings, voluntary in homes. People are instructed to stay at home in their bubble other than for essential personal movement and safe recreational activity is allowed in local areas. Travel is severely limited and all gatherings are cancelled and all public venues are closed. Businesses are closed except for essential services.