BOSTON (CBS) — The MBTA restored more service on rail lines Sunday morning after weeks of limited operation that has frustrated riders.

MBTA officials said that service has been fully restored on the Braintree branch of the Red Line and on the Green Line’s B Branch. That announcement came a day earlier than expected.

READ MORE: 'Frightening Anti-Semitism': Jewish Community Focused On Security After Texas Synagogue Hostage Situation

“Today marks a major step to getting the transit service our customers and expect and deserve back up and running,” said MBTA General Manager Beverly Scott in a statement.  “Despite the major setbacks the weather has dealt us, I want to thank Governor Baker for playing a vital role in the coordination of resources and assistance we had to help expedite the restoration of service.  I also want to express our appreciation for our customers and say thank you for your loyalty.”

Read: Gov. Baker Assembles Special Commission To Fix MBTA Woes

READ MORE: Stoneham Police Officer Needs 30 Stitches To Face And Head After Being Attacked By Dog

MBTA service has been severely limited or shut down entirely during a period of historic snow and cold in Massachusetts. Scott has also said she will resign amid harsh criticism of the T’s performance from the governor and commuters.

The MBTA also said it is increasing call center resources by about 25 percent to reduce customer wait times. That number is 617-22-3200.

MORE NEWS: Eversource Prepares For 'Kitchen Sink' Storm Expected To Bring Snow, Rain And Wind To New England

MBTA “Ambassadors” will also be at key stations during rush hour starting Monday to assist riders, officials said.