It was obvious from Wednesday that the lockdown was not going to be "short" and so it came as a surprise to some that Cabinet did not also extend Auckland's lockdown when it met on Friday to decide on the rest of the country.
Ahead of that meeting, director general of health Ashley Bloomfield advised Cabinet to extend Auckland lockdown out to August 31.
Instead, Ardern simply indicated Auckland's lockdown could also be extended when Cabinet next met on Monday.
She did not spell out why she did not go for the August 31 recommendation then and there.
The likely explanation is Ardern wanted to wait to see how fast and big the cluster was growing, and, critically, whether it was spreading even under lockdown.
It would suggest Ardern is considering a much longer lockdown from next Tuesday, rather than extending it week by week if things were not improving.
Such a decision would include flexibility to move down levels if we returned to a string of zero cases, as has happened in the past.
Some of the information that will be critical in that decision could be released today.
There are now more than 50 cases in the outbreak of Delta but as yet little information has been made public about the routes the virus is taking, or whether any particular event or place is shaping up to be a super-spreader event.
The information on how or where those people got the virus and how they all link up remains scarce.
There are any number of potential super-spreader options on the list, on the face of it. There are cases from at least four high schools, and two universities. There were crowded lecture theatres and parties.
There was a large awards event at Spark Arena.
We know which workplaces or schools there were cases at but we do not know how many cases there are at those places. We do not know whether there are multiple cases at any school.
Nor do we know how many caught it simply from being at an event or location, rather than by being friend or family with an infected person.
Asked yesterday, Ardern said health officials might be able to offer more information today on whether numbers were particularly high at any one event or place.
It is information that needs to be shared as quickly as possible, especially as the numbers of those deemed close contacts ratchets up to the 10,000 people mark.
Ardern voiced some concern that putting too much focus on super-spreader events would make contacts from other locations less inclined to get tested.
But there is a compelling reason people need to know whether some locations of interest are returning a higher number of positive cases.
Thousands of people have now been asked to get tested.
The sheer numbers mean that getting a test has been an arduous exercise for many, requiring hours and hours in queues.
For all those who do stick it out, there will be those who simply give up and go home or decide to wait until the demand dies down to get their test. They will be more inclined to join those queues if they know they were at a high-risk location.
A delay in identifying those cases means a delay in identifying other people and locations who may have been exposed in the meantime.
Health officials probably already have a fair inkling of the danger spots.
If so, they should move quickly to name them even if it caveated.
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