He said there were around 300 staff at the Auckland office, which also has contracts for Air New Zealand and Nespresso. A contract with Spark was lost earlier this year.
All staff working on the Apple account were told yesterday afternoon. One of the insiders said they were left with the impression they would be left jobless if they did not find outside work by February 2.
He said Apple had been putting the heat on over scores from customer satisfaction surveys.
The multinational Concentrix holds contracts with Apple around the world. One of the insiders expected that a Concentrix office in Brisbane would pick up the slack.
Roberts refused to confirm if Apple was the lost client, citing confidentiality, but said, "Concentrix has been informed that there is no longer a requirement for one of our lines of business operating from our Auckland site. As this change is likely to affect a number of roles, we have started consultation with our affected staff to elicit their feedback and will work with them to identify the best way forward."
The country manager said no final decisions have been made, and that some staff working on the client's accounts could potentially be redeployed to other roles between now and the new year.
"Our business is experiencing growth, which is creating opportunities in other lines of business."
Concentrix nested itself at Unitec after winning a major business process outsourcing (BPO) deal with the Auckland polytech. Unitec has endeavoured to build a tech hub, with IBM also moving in.
However, the outsourcing deal was partially reversed in October last year, with student enrolment and other functions moving back inhouse. A sweeping review and financial overhaul continues at the troubled polytech.
Concentrix is a subsidiary of the New York Stock Exchange-listed Synnex.
In June it bought Convergys in a deal that it said made it the world's second-largest BPO company. Convergys, in turn, bought part of NZ company Datacom's helpdesk business in 2013.
Apple did not immediately respond to a request for comment.