THE MBTA OVERSIGHT BOARD on Monday put on hold a plan to add additional bus routes to mitigate the cancellation of late-night service until a more sweeping proposal for all-night bus service can be vetted.

The T’s Fiscal Management and Control Board was intrigued enough by a proposal put forth on March 30 in CommonWealth magazine by three transportation advocates – Ari Ofsevit, Jeremy Mendelson, and James Aloisi – to put on hold a staff recommendation to add the bus routes.

In their article, the three advocates suggested expanding an existing bus service for early-morning workers to provide all-night service every day of the week. The proposal called for selected buses to run on an hourly basis during the night from most areas served by the T to a central point such as Copley Square, where passengers could make connections to their final destination. One bus route would run to Logan Airport, where nearly half of all shifts begin before MBTA service starts. The advocates said they believed the expanded service “would cost on the order of $1 million per year.”

While state transportation officials were skeptical of the $1 million figure, members of the control board wanted more information about the proposal before taking any action. They asked T officials to examine the cost of the proposed service and its ability to serve low-income and minority riders.

The debate rekindled a sensitive subject for the T. The transit agency last month canceled its late-night service on weekend nights because of concerns about the high cost. Just before the service was shut down, the Federal Transit Administration said the T needed to analyze whether cancellation of the service would disproportionately impact low-income and minority riders. The T had taken the view that cancellation of the late-night weekend service wasn’t a major service change that required review.

John Englander, the general counsel of the MBTA, said at Monday’s meeting of the control board that the impact of the service cancellation can be analyzed two ways: either on the population at large or just the T’s riders. He said a population analysis showed no disproportionate impact on minority and low-income residents, while the analysis of riders did show a disproportionate impact. As a result, Englander said, the T was not required to take any action to mitigate the impact of its late-night service cancellation, but could take voluntary steps to ease the impact.

Charles Planck, the T’s deputy chief operating officer, outlined a voluntary mitigation plan that called for additional service on seven bus routes on some mornings between 5 a.m. and 7 a.m. and on weekends. Planck said the mitigation plan, with a cost of more than $562,000, would have to be approved by the board by April 15 to be implemented by the T on June 25.

Under questioning from control board members, Planck said the all-night, all-week service proposed by the three transportation advocates had attracted a lot of interest but not been vetted by T officials. State Transportation Secretary Stephanie Pollack suggested the cost of the all-night service proposal would be a lot more than the bus route additions being proposed by the T. “It doesn’t seem like it would be able to be done for $1 million,” Pollack said of the proposal by the advocates.

Brian Lang, a member of the control board, said the T couldn’t afford to do both the T’s proposed mitigation effort and the all-night service, so he urged tabling the T’s proposal until the all-night service could be fully vetted.

Rafael Mares, a vice president at the Conservation Law Foundation said the two options were not incompatible. He said the T could add the bus routes now and, if the all-night approach panned out, add it on later. By taking no action until a full cost analysis of the all-night service is done, Mares said, low-income and minority riders of the T could suffer without any late-night service until the fall.

“That’s a long time to wait,” he said.