South Australia’s police commissioner has apologised for what he says was a communication breakdown that caused passengers from Sydney, Wollongong and the Central Coast to go into quarantine on Sunday night even though they arrived hours before the midnight border closure.

Restrictions are back in place for travellers arriving in SA from NSW as concern mounts over Sydney’s coronavirus cluster.

Arrivals into Adelaide Airport from NSW claim they were being told they had to return to Sydney or go into 14 days’ quarantine on Sunday night, despite arriving hours before South Australia’s midnight border closure.

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Many travellers say they were confused and some say they were left on the tarmac for hours while authorities processed arrivals.

Some people have also reported being turned back at the South Australian border when they attempted to drive across several hours before the border shut.

Commissioner Grant Stevens, who sets border directions as the state coordinator, said people would be getting phone calls on Monday from police officers letting them know that they did not need to quarantine or leave the state.

“Anyone who is already in South Australia from the Greater Sydney area is simply required to get a COVID test on day five and day 12 after the first [day one] test,” he told ABC Radio Adelaide.

Flights from Adelaide to Sydney were selling for above $1,000. Photo: ABC News: Dean Faulkner

Just after midnight, South Australia Police issued a statement, saying travellers who arrived from Greater Sydney before midnight did not need to quarantine.

It said that from midnight, all arrivals from the greater Sydney area, along with the Central Coast and Wollongong, needed to quarantine for two weeks and anyone who had been in the Northern Beaches area of Sydney was barred from entering the state.

People in quarantine will be tested three times for the virus – on arrival, on day five and on day 12 of quarantine.

People arriving from regional NSW will be required to have a test but do not need to isolate.

Police are at the SA-NSW border checking where people have come from and visited. Photo: ABC Broken Hill: Saskia Mabin

Confusion from SA Health

Earlier on Monday, SA Deputy Chief Public Health Officer Mike Cusack sowed confusion by saying people who had been in the greater Sydney area since December 11, or the Central Coast and Wollongong since December 20, should do a 14-day quarantine, backdated to when they left those cities.

“Based on what we know we now believe, if you have been in Sydney on those dates … you are considered to have been in a high-risk location,” Dr Cusack said.

“On that basis, you need to undertake a 14-day period of quarantine.”

Commissioner Stevens said he would be trying to work out how the wrong messages spread.

“That’s little comfort for people who turned around and decided not to come into South Australia yesterday and clearly we didn’t want this to happen,” he said.

“The instructions that came out of my meeting with SA Health and the press conference yesterday was you didn’t have to quarantine if you came in before midnight, but you will have to have PCR test on day one, day five and day 12.”

Recently removed checkpoints are back in place at the SA-NSW border, where travellers are also being tested before entering South Australia.

Conflicting messages at airport

Brinly, who did not want his last name published, was coming home to Adelaide for Christmas to visit family until mid-January.

He told ABC News that 15 people identified as COVID marshals came onto his Virgin Australia flight from Sydney on Sunday night, along with about six or seven police officers.

He said they were asking where people were from and if they said Sydney were told they would have to quarantine or fly back.

He was made to book a flight back to Sydney and did so while he waited there.

“I have never ever been to the Northern Beaches in my life and never been to any of those venues,” Brinly said.

“I work from home, so have been home all week mostly.

“She then made me buy a return ticket and made sure I would isolate either in a quarantine hotel [in Adelaide overnight] or in an isolated room [with a] bathroom at a trusted relative’s house.

“I was then told it’s fine to get a Uber to the location, provided I sat in the back row.”

He had a flight to return to Sydney on Monday.

“If I knew a 14-day quarantine was required, I would have never stepped foot on the plane,” he said.

Another passenger, Holly, was told she needed to stay at a hotel to quarantine or return to Sydney but then after questioning the instructions was eventually allowed to come into Adelaide.

She was to get a test on Monday.

“These poor people who were just trying to do the right thing were just treated like second-class citizens in a situation where the information was incorrect,” Holly said.

“When we asked for clarity on that, they couldn’t provide it, so, yeah, a pretty disappointing situation.”

Tweet from @SAHealth

Incorrect information at border

Michael’s brother and his husband were driving to South Australia for a Christmas gathering.

He said they made a “quick dash” to the border but were told about 8pm on Sunday to turn around.

“It’s disappointing and I can understand where police are coming from I guess, but they had come over on the understanding that they could get through to the border if they got there before midnight,” Michael said.

“Then to be told not, it’s an expensive exercise in terms of petrol and accommodation.

“It’s very disappointing all round.”

Peter said his daughter was “sprinting” for the border from Sydney with her young family and arrived at Pinnaroo about 7.30pm.

They were told to do 14 days’ quarantine.

“That came as a complete surprise,” he said.

They are now self-isolating at Port Willunga with plans to return to Sydney.

-ABC