DETROIT — General Motors will continue producing the Cadillac CT6 and Chevrolet Impala large sedans until January 2020 at its Detroit-Hamtramck assembly plant in Michigan.

The company was scheduled to end output of the cars in June as part of restructuring plans announced in November to realign North American manufacturing plants amid a broad consumer shift to light trucks from cars.

The change in production plans, according to GM , was made to match supply with demand and extend the availability of advanced technology features on the CT6 such as a Blackwing twin-turbo V-8 engine and Super Cruise driver assistance system.

The extension does not change the future status of the Detroit-Hamtramck plant after January 2020, according to GM. The factory is one of four in the U.S . that is potentially slated for closure since GM said in November the sites would not be allocated new products after 2019.

GM said it notified employees, suppliers and dealers of the change on Friday.

The terms of any U.S. plant closing must be negotiated between the UAW and GM, and the two sides will bargain over a new national labor pact covering wages, benefits and job security later this year.

The union's current four-year contract ends in September, several months before CT6 and Impala output will end.

The UAW, in a joint statement from President Gary Jones and Vice President Terry Dittes, said Friday the announcement is welcomed and a “sense of relief’ for workers and their families. However, they reiterated that the union will “leave no stone unturned in seeking to keep” U.S. plants open.

The other plants potentially slated for closure include Lordstown Assembly in Ohio and powertrain factories in Michigan and Maryland.

Roughly 3,300 UAW members are expected to be impacted by GM's plans, many of whom were retirement eligible or have been placed in jobs at other company plants. GM also plans to end production at Oshawa Assembly in Ontario by the end of the year.

GM previously extended production of the Chevrolet Cruze at the Lordstown assembly plant until March 8, a week later than initially expected. The scheduled end of production – scattered through the year – has not changed for the powertrain plants or Oshawa assembly, according to GM.

GM discontinued output of the Buick LaCrosse sedan and Chevrolet Volt plug-in hybrid vehicle at the Detroit Hamtramck plant this week -- several weeks ahead of schedule. About 775 people, including 700 UAW workers, are expected to continue working at Detroit-Hamtramck until production of the CT6 and Impala end in January.

GM President Mark Reuss and Cadillac President Steve Carlisle previously told Automotive News that they were evaluating options to keep the brand's flagship sedan on sale in the U.S. following its scheduled end of production.

U.S. sales of the CT6 dropped 8.3 percent to fewer than 10,000 in 2018. The Automotive News Data Center estimates sales of the luxury sedan last month rose 1.3 percent compared to January 2018.

Domestic sales of the Impala fell 26 percent to less than 57,000 last year. January sales rose an estimated 32 percent.

The Automotive News Data Center estimates there was a 79-day supply of the CT6 at the end of January, while there was only a 42-day supply of the Impala – far below what’s considered healthy levels.