"Basically they're very positive to all the boats coming down in 2021," he said.
"At this stage they've told us all nine yachts are coming, and they'll bring ... their support vessels."
The fleet would likely be in New Zealand waters for around six months, with Mair estimating they will arrive as early as October 2020 and stay through to until March 2021, racing in regattas in the Bay of Islands and Auckland.
"They come down with a huge crew — there's a lot of money that goes into it, so we really want to give them as much time as possible," said Mair.
The spectacular J-Class yachts, which were first raced in the 1930s, were one of the highlights of the racing programme at the 35th America's Cup in Bermuda.
"You've basically got enormous boats with ... 30 crew running around," said Mair.
"Whereas with the [America's Cup catamarans] you didn't see any sails going up and down, the J-Class boats you see sails the size of football fields getting lifted and lowered — it's just a totally different scale".
Mair believed the J-Class fleet will bring a carnival-like feel to the event.
"A lot of the super yachts are just hotels on the water. But J-Class boats, when the public [look at these boats they] appreciate the love that goes into them — that real classic style.
"You've got all those crew milling about, you've got sails being carried on and off — [it's a] real regatta feel."
Mair said the RNZYS have also applied for a royal visit in 2021 through the Ministry of Foreign Affairs and Trade, while there could also be a visit from overseas naval frigates.