The Metropolitan Transportation Authority had good news on Monday for subway riders worried about the shutdown of the L train: The closing will be shorter than expected.

The authority’s board voted to approve a $477 million contract to close the L train tunnel between Brooklyn and Manhattan for 15 months to repair damage caused by Hurricane Sandy — instead of 18 months as originally planned. The work is set to begin in April 2019.

After several board members raised concerns about a company that was awarded the contract, Judlau Contracting, officials assured the board that the company was the best choice for the project and would finish the work on time.

“I expect this project to be completed in 15 months,” said Lawrence S. Schwartz, an authority board member. “I want to make sure that Judlau and everybody else who is going to be involved on this project understands that it will not be tolerated or accepted to be 15 months and one day.”