"On behalf of the Board, I would like to thank Simon for his contribution to Synlait," McGilvary said.
The announcement was published on the Australian Stock Exchange on Monday.
Robertson’s departure comes a year after he took the chairmanship role over from one of the company's founders John Penno.
Robertson joined Synlait’s board in 2020 and is a professional company director. McGilvary has been on the board since January 2022.
Synlait is trying to sell its Dairyworks business to pay down debt. But in the meantime, its biggest customer, a2 Milk, is now looking to reduce its reliance on Synlait by investing more in its Southland plant.
Last month a2 Milk cancelled Synlait's exclusive supply rights for stages one to three infant formula, saying the company's delivery levels fell below the required standard.
Synlait, which has its headquarters in Dunsandel, and a2 Milk announced last week they were heading to binding arbitration over Synlait's cancelled supply agreement.
Synlait has disputed a2 has the right to cancel the exclusivity arrangement. The company will continue to make infant formula for a2 under its three-year rolling-term contract.
-RNZ and Star News
