The plant's future had been in doubt since Polestar admitted in December that it was a loss-making business that couldn't be sutained in its current form.
GPMU deputy general secretary Tony Burke said workers at the site had voted "overwhelmingly" in favour of a package that had been put together through negotiations last week. He declined to reveal details of the plan.
However, the plant's bindery is still poised to close. Last month the group started a 30-day consultation period with the GPMU after failing to find a solution to stem "massive" losses suffered by Greaves' bindery.
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