The temporary tightening of restrictions from Thursday at 5pm to 12.01am on Monday include a limit on visitors to aged care facilities.

Visitors to aged care facilities will be limited to two people, which is bad news with Mother's Day coming on Sunday.

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Warrigal CEO Mark Sewell admitted it was "very annoying" that Mother's Day would be affected.

"A lot of people come in on Mother's Day and we often get our homes full of relatives and kids and grandkids because sometimes they can't take mum home because mum's in a wheelchair or she needs a lot of medical or nursing care," Mr Sewell said.

"If they're coming into the care home it's only two people visiting on the day."

He said Mother's Day could be better for those relatives who are able to take their mum home, due to the fact that 20 visitors - including children - are allowed in houses.

Mr Sewell said the return of the restrictions came after "six weeks of freedom" following their lifting by the government in March.

After almost a year of restrictions at aged care homes, Mr Sewell said the staff knew what to do on Thursday.

"I'm just leaving one of our aged care homes and everyone is just completely familiar with what to do - the two visits per day by relatives, the extra screening and the facemask wearing because they've been doing it for a long time," Mr Sewell said.

"There's a few groans and disappointments that it's back on and we haven't stayed free from it but I think most realists knew that it was likely to happen again.

"Organisations like Warrigal have been telling everyone we're still in a pandemic. We have got winter to get through and we don't have enough vaccine rates anyway so the restrictions will probably be applied at some time."

Mr Sewell also noted that from June 1, all visitors will be required to show proof they have had a flu vaccination before being allowed inside, as per a NSW Health directive.

The restrictions also affect all indoor venues, including retail, hospitals, aged care facilities and theatres, where masks are mandatory.

But the restrictions hadn't stopped the So Popera production of the musical Jersey Boys at the WIN Entertainment Centre from going ahead.

The show premiered on Thursday and runs until Sunday and producer Mal Copeland said the performance would go on.

"At this stage we are all go ahead," Mr Copeland said on Thursday afternoon.

"We've just come out of the meeting with the venue and they've been in contact with Venues NSW as well as NSW Health and we are good to go just with some minor restrictions."

As well as the mandatory facemasks the venue and patrons will also have to abide by the ban on drinking while standing up.

There is a ban on singing at indoor venues, but Mr Copeland said that applied to audiences and not the performers onstage.

At this stage there was no restrictions on the number of patrons in the theatre but, given the production is only using a section of the total seating at the entertainment centre, there was scope for change if necessary.

Mr Copeland said he hadn't been concerned about Jersey Boys being cancelled at the last minute.

"It was something we just knew we had to work through and talk to the appropriate people which we've done and we've done that well," he said.

However, the Yours and Owls all-ages sideshow scheduled for Saturday at the University of Wollongong has been postponed due to the restrictions.

"To say we are bummed would be a massive understatement," the organisers posted on Instagram, " but we have all been here before and we know the steps, so please follow the guidelines being asked and hopefully we are all back to normality come Monday night."

The organisers said they planned to make another announcement about the all-ages show on Tuesday.