Ford may cut a shift at the factory responsible for building the F-150 Lightning due to an alleged drop in demand for the electric pickup truck.

A letter sent out by the UAW chapter official who represents workers at the Michigan factory responsible for building the truck claims that the firm will cancel a shift and wants to increase production of its combustion-powered pickups. It has been 18 months since production of the F-150 Lightning commenced and already, sales appear to have dropped significantly.

“It doesn’t take a rocket scientist to figure out that our sales for the Lightning have tanked,” the official wrote.

Read: Ford’s F-150 Lightning Plant Is Back Online, Targeting Annual Capacity Of 150,000 Units

 Ford Could Cut F-150 Lightning Production Due To Waning Demand

The Wall Street Journal spoke with Ford about the letter. The car manufacturer declined to comment on the possibility of dropping a shift on a long-term basis but did say that supply-chain disruptions and quality checks mean there will be schedule changes in the short term. The Ford spokeswoman added that it is these constraints that have forced it to temporarily cut a shift impacting 700 workers.

Soon after launching the F-150 Lightning, Ford increased its production plans twice with the intention of building 150,000 examples annually. However, the carmaker reported a 45.8% drop in sales of the electric pickup in the U.S. through the third quarter. This came despite Ford cutting prices of certain F-150 Lightning models by as much as $10,000 in July, reversing price increases it made earlier in the year due to the soaring cost of raw materials.

Ford is aiming to produce 600,000 EVs annually by the end of 2024, some 12 months after it had initially planned to reach that figure. Chief executive Jim Farley said this was because the firm expects the “EV market to remain volatile until the winners and losers shake out.”

 Ford Could Cut F-150 Lightning Production Due To Waning Demand