BOSTON (SHNS) – The Chinese firm responsible for building new MBTA Orange and Red Line trains is still crafting an updated schedule for the project after multiple delays, and T officials appear pleased with how well the vehicles have been performing lately.

MBTA General Manager Phil Eng told the agency’s board that CRRC has “strengthened” its quality assurance team in the wake of numerous issues reported at its Springfield manufacturing plant. Eng said he, Deputy General Manager Jeff Gonneville, Transportation Secretary Gina Fiandaca, Economic Development Secretary Yvonne Hao and Undersecretary of Transportation Monica Tibbits-Nutt held a virtual meeting last week with CRRC’s chairman, describing it as “productive.”

“They reiterated their commitment to this project, to improving production, maintaining quality and in turn, we reconfirmed our continued partnership and full attention to this project as well,” Eng said at Thursday’s board meeting.

The pricey project to replace the Red and Orange Line fleets with new CRRC cars, which began under former Gov. Deval Patrick, has run into multiple problems. Gonneville, who served as interim general manager for a few months before Eng took over, said in January that even the most recent forecast that the last Orange Line cars would be delivered by December 2023 and the final Red Line cars by September 2026 was likely to change.

Eng said Thursday that CRRC is still crafting a “revised schedule, which we will share with everyone upon completion.” A new Orange Line train will enter service on Aug. 27, reducing headways on that line to nine minutes at peak travel times, he added.

Although problems and malfunctions involving CRRC-built trains have been regularly publicized, Eng said Thursday that the vehicles are in fact performing better than expected. The new Type 14 Orange Line cars are averaging about 114,000 miles traveled between failures, Eng said. That’s more than a quarter more than the contract requirement of achieving 90,000 miles between failures, and nearly four times better than older Type 12 vehicles that averaged 30,000 miles between failures.

“While we’re proud of the performance of the accepted fleet, we know that the current schedule needs to be improved, and we continue at the highest level tackling these challenges to improve production,” Eng said.