Keolis is under even more pressure as the MBTA commuter rail's Worcester line is plagued with delays.
According to the Boston Herald, two out of every five trains have run late over the last month and less than half have been on time during the morning commute in November.
Keolis has since launched a working group to identify its problems and propose possible solutions.
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According to "T" data, the Worcester line, which runs through Framingham, Newton, and other communities, generally carries the second most daily commuters behind the Providence/Stoughton line.