The Employment Court has ordered Affco Wairoa to re-instate 160 union members, locked out for six months, to return to work with their normal shifts and recognition of seniority.
The dispute started when the NZ Meat Workers Union and Affco failed to renegotiate a collective agreement that expired in 2013.
The union sought a nil wage increase and for the agreement to roll over.
Company changes included removal of a seniority clause, which gave workers with the greatest experience first refusal of jobs at the start of a new season.
The company walked away from negotiations citing recent amendments to the Employment Relations Act.
Meat Workers Union organising director Darien Fenton said workers were hopeful of a return to work after a November Employment Court ruling that the lockout was unlawful.
"The company's remedy was to have the entire Wairoa union membership consigned to the night shift, regardless of the workers' employment agreement rights, previous shifts and seniority provisions."
Affco Meat Company general manager Andy Leonard said the latest ruling would be appealed to the Court of Appeal.
"The company maintains it has not locked these workers out," he said.
"They have had opportunities to work at the plant since it opened this season."
The court has ordered a return to check for compliance on February 23.
Union delegate Peter Amato said locked out workers had been "doing it hard" after company "punishment" for solidarity.
"The wives of these guys has been the strength of our union," he said.
"There was nothing but smiley faces at the Resource Centre today."