The Herald understands Tuivaiti is yet to secure a contract elsewhere, with the new, as-yet unnamed, Auckland franchise also unable to offer the 24-test Silver Fern place on their roster.
The news came as a triple blow to Tuivaiti, who last week missed selection in the Silver Ferns team for the Quad Series.
There are still options open to the 29-year-old, who has consistently been among the most accurate shooters in the ANZ Championship over the past nine seasons, with the Central Pulse shaping up as the best fit.
The Pulse, coached by Silver Ferns assistant Yvette McCausland-Durie, are a largely young and inexperienced side and would benefit from Tuivaiti's significant scoring power. There is also likely to be a vacancy in their shooting end with Maia Wilson - the teenage star that effectively shut Tuivaiti out of the Ferns line-up - expected to link up with the new Auckland team.
It appears there will be several shooters on the move next season. Bailey Mes, the Ferns starting shooter, is tipped to rejoin the Mystics next year after two seasons with the Mainland Tactix.
Despite rumours linking Mes to the Mystics, Paterson maintained Tuivaiti's departure from the franchise was entirely on her own terms.
"She thought to herself if there was ever going to be a time to make a change this would be the time with the new competition coming into play next season," said Paterson.
"While we appreciate her reasons for moving on, it is a really sad day for us. Cat's been such a key part of the team for so long and brings so much character and energy to the group."