As much of New Zealand eagerly awaits news about an alert level change today, it remains unclear how police will manage checkpoints at a level 2 and 4 split.

Police said yesterday checkpoints operating at both north and south of Auckland have been running smoothly since Auckland was broken away from the rest of the country which currently sits in level 3.

Nearly 14,000 vehicles have been stopped at the 10 checkpoints around Auckland.

A total of 444 vehicles were turned away for non-essential travel in the south - less than 4 per cent of all motorists - and 24 in the north.

Prime Minister Jacinda Ardern will announce whether everywhere apart from Auckland will move down to level 2 at a press conference at 4pm this afternoon.

The number of Covid cases has remained low over the weekend, both times numbers have been in their 20s.

Suspected source of outbreak - vaccination centre closes

Meanwhile the vaccination centre next to the Crowne Plaza is being moved.

The Crowne Plaza has been undergoing a review after it was revealed there were two public walkways in and around the managed isolation facility.

From Wednesday, the new vaccination centre will operate at 35 Graham St in Auckland's CBD.

A Northern Region Health Coordination Centre spokesperson says they will have the capacity to vaccinate about 400 more people a day than at the current site.

They say the new location will eliminate any concerns people may have about getting vaccinated near the Crowne Plaza Hotel.

Of the 20 new Covid cases announced yesterday, 30 per cent had exposure events, while 70 per cent were in isolation for their whole infectious period.

The country's first Covid Delta-strain related death was also announced yesterday - a woman in her 90s at North Shore Hospital.

The Ministry of Health said she had a number of underlying conditions.

The last Covid death in New Zealand was in February this year. That person also died in North Shore Hospital.

Meanwhile, the daughter of a 91-year-old patient at Middlemore, who was on the same ward as a Covid-positive patient, said there had been no explanation from Counties Manukau DHB about what had happened.

The daughter, named Fiona, told Breakfast a doctor was due to speak to the family today, she said, however they were "incredibly upset" about the possible "huge number" of hospital staff, including doctors and nurses to cleaners, who could have been exposed to the patient.

She wanted to know why Middlemore did not have a procedure to immediately isolate the patient to avoid further risk.

Deputy PM Grant Robertson told Breakfast the Covid-positive person in Middlemore entered the hospital on an unrelated matter.

After symptoms emerged they tested positive.

Other patients and staff who were on the ward were being tested, he said.

He didn't have detailed information but said there would no doubt be more to say at this afternoon's press conference.

Pressed on why patients were left in the room for up to eight hours after exposure, Robertson said hospitals were very clear on infection prevention protocols and had been "brilliant" so far. But more questions would be asked.

As for alert levels, Robertson said they would be keeping a keen eye on new cases and wastewater results.

He said while things were looking positive he pointed to Victoria which had got down to a low number of cases - but was now seeing an increase.

Testing numbers had dropped substantially and that was a concern, especially in Auckland, Robertson said.

He urged anyone with cold-like symptoms to get a test.

He warned yesterday that the highly infectious Delta variant could have a long tail, with positive cases continuing in Auckland for weeks.

Covid-19 modeller Professor Shaun Hendy said yesterday they had seen a clear downward trend for a week and felt reasonably confident that alert level 4 is doing its job against Delta.

A "September exit [from level 4] is certainly looking more possible, but the risk still remains of a long tail as we experienced last year in the 2020 August outbreak", Hendy said.

As for NZ's R rating, Robertson told Mike Hosking on Newstalk ZB it was still below zero, and likely around the 0.6 and 0.8 range.

Robertson wouldn't comment about moving down alert levels but added "it has been an encouraging period of time, Mike".

"Auckland appears to have started to come down on a trend ... we will announce that this afternoon."

Robertson was unsure if the 91-year-old who died of Covid was vaccinated but said vaccination rates in that age group were "very high".