Vodafone NZ is currently undergoing a major restructure.
A spokeswoman said New Zealand employees were offered the opportunity to express interest in taking voluntary redundancy on February 14. Unite were advised the same day.
"Front line call centre and retail staff were exempted from this offer to avoid any disruption to customer service while we work through our company-wide review of our operating model. Voluntary redundancy is a separate exercise to any restructure proposals that Vodafone may subsequently table.
"As and when we design a restructure proposal for any specific area of the business and are ready to consult with employees, we will engage with Unite and follow a full, formal consultation process."
New chief executive Jason Paris says rank-and-file staff will find out how they are affected by the end of this month.
Insiders have told the Herald there is a broad expectation that around 400 of 2800 roles could go.
Paris stressed in an earlier interview that there was no set number. Different departments would gain or lose staff depending on the outcome of the ongoing review.
And he while he has acknowledged the possibility that call centre jobs could be offshored, Paris also said no decision would be made that would hurt customer service.
As part of an international company, Vodafone NZ was able to tap into its parent's "Centres of Excellence" in other territories.
Paris says Vodafone NZ fell short of targets last year. His brief is to get the subsidiary into shape this year for an IPO in early 2020.
The telco needs to better its bottom line, but also free up funds for investment in new technologies, the chief executive says.
Earlier, he told the Herald, "As a proud and passionate New Zealander my preference is to keep roles in NZ, but when the customer service is the same or better and at a much lower cost then it's tough to ignore this option. Just to clarify that in these overseas call centres we pay the agents well based on their local market and cost of living."
Paris also saw more automation and chat bots as part of the solution, in some contexts.
"When you're dealing with an organisation, you'd much rather deal with us for an app or digital channels than talk to people, in the main, unless it's a big decision or a complex problem," he said.
Wang says it's rich for Vodafone to cut staff after raising the price of all its broadband plans by $3 a month in March.
Paris said earlier that his company was passing on cumulative price increases by wholesaler Chorus.