(Reuters) - Fitch Ratings lowered its 2024 forecasts for Boeing's ( BA ) aircraft delivery and free cash flow on Friday as the planemaker grapples with investigations and slumping production of its strongest-selling jet.

"The delivery forecasts were affected by the Civil Aviation Administration of China's (CAAC) decision to restrict certain aircraft model deliveries to Chinese customers while it requests additional documentation regarding voice recorder and battery information," Fitch said.

The forecast revision also reflects the Federal AviationAdministration's decision to maintain oversight within Boeing's ( BA ) factories while individually certifying newly produced aircraft, the agency said.

The rating agency forecasts between 350-370 737 MAX deliveries and about 65-70 787 deliveries in 2024, below previous expectations of about 400 and 75, respectively.

Fitch also expects modestly negative free cash flow during 2024, compared to previous expectations of breakeven to positive.

Fitch does not currently expect these adjustments to result in rating changes.