Travelling with her will be DJ Shane Schwalger and festival helpers - Miss Knap's daughter Krisuane Knap, Marie Hodge, Leon Winiata and Wi and Mary-Anne Kapene.
The festival starts with a powhiri at 8.30am and will feature the biggest haka challenge seen in North Queensland - Cairns versusTownsville - two kapa haka cultural groups, a kohanga reo performance, hangi sales, market stalls, food, Maori merchandise and arts, a New Zealand residents' challenge, men's and women's rugby union and league matches, games for kids and the world's biggest water slide.
Among the line-up will be bands Sun Salute and Paua as well as Maori performer Scratch Grey, who now lives in Australia.
Knap, who lived in Australia between 2008 and 2014, said Waitangi Day in Australia was a different vibe to that in New Zealand.
"It's huge over there, it goes on for a month."
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She said the segregation and land issues were often put to one side in Australia and instead Maori living there chose to spend the day remembering their whanau, celebrating being Maori and spending it with as many Kiwis as possible.
"People have said 'you guys [in Australia] do a celebration for Waitangi Day bigger than they do in New Zealand. It is about togetherness there whether you are Maori or Pakeha. Everyone comes together and the Australians love it."
Among those running the festival is former Rotorua man Rob Hodge, who asked Knap and her group to attend this year.
"It's a real honour to be in a concert over there ... They have done it before but it's the first time they are doing it on this scale."
Knap will bring to the show her special Maori-style humour and will take the opportunity to showcase as many Te Arawa clothing items as possible.
"I've got it worked out. I'm going to wear my Tunohopu T shirt, my Te Arawa cap, I've got T shirts from Rotorua Summer Seafood Festival, Whaka village, Matakana Island and Te Roro o te Rangi. I plan to change every hour," she said.
She said while it would be great to be back in Australia, she didn't plan to go back to live.
"A lot of my Aussie mates ask me when am I coming home to Aussie but I wake up and see my mountain and I look to the lake and see Mokoia Island. I love being home but I do love Aussie."
She was also now able to do the two things she loves - working, as a hostess/bar manager at Ponsonby Road Lounge Bar, and gigging.
Before she left for Australia she was doing music full time and she admitted it became a little stressful always ensuring she had enough work to make a living.
But now, she has the benefits of both and enjoys it, plus once a month she kills two birds with one stone and performs at Ponsonby Road Lounge Bar.
Knap and her group leave for Cairns on Thursday and she hopes it won't be the last time she gets to travel back to Australia to celebrate Waitangi.
"Cousin Melissa Waaka wants to book me in for a Waitangi celebration in Sydney next year. That'll be cool."