Starting on Aug. 24, the changes will include more frequent Red and Orange line trains, especially during peak weekday times.

A partial shutdown of the Red Line began Thursday night and will remain in effect through Sunday, according to the MBTA.

Green Line service through downtown Boston will shut down Wednesday night at 8 p.m. through Sunday night, leaving commuters to rely on the Orange Line and shuttle buses, MBTA officials said.

Metro planned to bring faster, smoother automated trains to the system’s Green Line this weekend. But the agency is being blocked by its safety watchdog, which said the rail system cannot expand ...

In December, the Red Line was the first to start using automation again. Now, the Green and Yellow lines will be the next phase of implementation in a plan to bring ATO back to all train lines.