"The bulk of the work is done to get the concert going and getting tickets on sale and sold," he said. "Once you get down to this stage, he's got all his people, none of them are working, everyone's available, and they're just waiting for the call."
The concerts are, however, locked into a tour, and it would not be viable to stage just the New Zealand segment, in which there is also a concert in Dunedin.
As for a postponement, anything's possible, including Rod Stewart still touring after he turns 76 in January.
Mission Estate Winery CEO Peter Holley said he's waiting for "feedback from the US", with a lot of uncertainties, including whether Rod Stewart can get into or leave the US, and whether the Covid-19 alert level in New Zealand would allow entry at the border or allow such a gathering as 20,000 people at a concert.
All are decisions that are unable to be made at present, and Holley doesn't expect the clearer picture for at least another month.
But a Rod Stewart pull-out won't necessarily mean it will be no-go at The Mission, which has already had a big year with the Michael Buble concert in January and two sold-out nights-out with Elton John in February.
Even if the borders are closed but large-scale gatherings can still be held in New Zealand there are options.
"There is a huge amount of talent in New Zealand."
"We will explore all options, but until we get a heads-up there's not a lot we can do," he said.
The lack of certainty also has the accommodation industry and service providers on the edge of their seats.
But Napier hotelier Rodney Green, who in 1999 opened the Bluewater Hotel which is booked out for both nights of Rod Stewart's nights on the town this year, says he doesn't want to think or talk about until he knows "exactly" what's happening.
"It's too hard to even ask the question or give an answer," he said. "It's a moving target."
Some hotels and motels have increased social housing guests overflowing from the housing and Covid-19 crises, which could raise issues if the Bay still has to accommodate the thousands of visitors expected for Stewart's only concerts in the North Island and probably his last in New Zealand.
Green said what will happen with the pandemic has "got nothing to do with New Zealand now, and added: "It's about the UK and the US."
"If we have a concert, we will cope," he said. "Hawke's Bay always does."
Meanwhile, Stewart also has a looming option in a Hollywood movie based on his half-century of concerts and his lifestyle, including three marriages, according to UK reports.
It was reported recently he reckons Harry Potter and Notting Hill star Rhys Ifans would be a good choice for the role of Rod Stewart, who with his management take the leading role in overseeing the production.
But British media were only speculating about possibilities for the roles of wives Alana Stewart, New Zealand model Rachel Hunter and current wife Penny Lancaster, and girlfriends such as Bond-girl Britt Ekland and model Kelly Emberg.