General Motors is stretching a production cutback at its Oshawa, Ontario factory until springtime, according to a memo distributed to Unifor union members who work at the plant.

Earlier this year, Oshawa Assembly began doing final assembly on current-generation Chevrolet Silverado and GMC Sierra pickup trucks while GM retools its Fort Wayne, Indiana factory to make the new-for-2019 Silverado —  something of a stop-gap for a factory that otherwise makes the slow-selling Chevrolet Impala and Cadillac XTS full-size sedans.

That process sees unfinished truck bodies shipped to Oshawa from Fort Wayne, where they are painted and go through the final assembly process.

Truck production began in January, and now The Globe and Mail has confirmed that GM is extending Oshawa's single shift operation until the end of May, with a second pickup shift to be added in June or July.

GM spokesperson Jennifer Wright told The Globe and Mail that "employment levels are expected to be retained" as the Oshawa plant picks up more truck production work.