THE MBTA’s OVERSIGHT BOARD, which has been urging the transit authority to think big when it comes to improving bus service, accused the agency of adopting a timid approach after hearing yet another update on its efforts Monday.

In its presentation to the Fiscal and Management Control Board, the T’s Better Bus team said it implemented 29 cost-neutral bus route changes on September 1, added 27 additional bus operators, and plans to do more of the same in December.

The team also said it expects to complete 22 dedicated bus lane improvements by early 2020 – a total of nearly 18 miles on roads in Boston, Cambridge, Somerville, Everett, and Arlington, including routes over the Massachusetts Avenue bridge spanning the Charles River and on Commonwealth Avenue in the Back Bay. On a number of the projects, a general travel lane instead of a parking lane is being repurposed to serve as the dedicated bus lane.

Kat Benesh, the T’s chief of operations strategy, policy, and oversight, said the agency plans to dedicate $10 million of capital funding to improving bus service. She said another $50 million is included in a bond bill pending before the Legislature.

“This is a very timid response,” said Joseph Aiello, the chair of the control board, who had urged the agency to use $50 million to create a fund that could cover 90 percent of the cost of a bus rapid transit buildout in communities that enlisted in the effort. In June, when he raised the idea, Aiello said the transit authority needed to think bigger, saying “we’ve got a mobility crisis here.”

On Monday, Aiello said there was no need to wait for the bond bill to pass since Transportation Secretary Stephanie Pollack has already said she has $1 billion in capital funds available for use.

“It’s ridiculous,” he said, voicing frustration that is rarely heard at the carefully choreographed meetings. “Bus people really get the short end of the stick.”

Pollack tried to play the role of peacemaker, saying T officials are focusing on areas of the Greater Boston area where dedicated bus lanes would have the biggest impact on the largest number of customers. She said T officials are worried that throwing $50 million on the table would solicit proposals that don’t fit the agency’s strategic goals. “What are we trying to do here?” she asked.

Aiello said the T could set parameters for the grants to make sure they achieve the greatest bang for the buck. But he said the T appeared to be taking a go-slow approach on speeding up bus service when circumstances dictate a more aggressive approach.

“We spend $200 million on rapid transit without even blinking and here we let people sit out in the cold,” he said, referring to buses whose on-time performance ranges between 76 percent and 78 percent (for key bus routes) and 60 percent to 67 percent for all other routes.

Monica Tibbits-Nutt, another member of the control board, said she was concerned that the T is moving way too slowly on improving bus service. She noted the route changes the T has implemented so far are all for off-peak service.

“I don’t know what is taking so long,” she said. “We get update after update but it doesn’t seem like anything is changing.”

Somerville Mayor Joseph Curtatone, who testified before the control board’s bus presentation, praised Aiello’s proposal for a $50 million challenge grant.  Speaking broadly about the T needing to do more, he called for systemic change and investments.

“We are in a crisis,” he said. “We cannot have incremental steps to take on a crisis.”

Benesh said part of the problem is that many municipalities, with the exception of Boston and a few others, are not equipped to implement dedicated bus lanes and other infrastructure improvements. Members of the control board said the T should maybe step in on behalf of many of the communities. Benesh acknowledged the T needs to move faster.

“It will never be fast enough for our riders,” she said.