IT WILL BE a summer of frustratingly long commutes for Red Line riders.

Ten days after a Red Line train derailed and crashed into three bungalows of signal equipment, MBTA officials announced it would take at least another 10 weeks of work until subway service returns to normal.

Workers removed the 50-year-old train from the track outside the JFK/UMass station less than a day after the roughly 6 a.m. derailment, and at the start of this week, service was restored along the Braintree branch, but at diminished speeds.

Friday’s announcement that normal service is more than two months away is sure to rankle passengers and further fuel calls for more aggressive steps to address shortcomings in the aging system.

Sen. John Keenan, a Quincy Democrat, who frequently uses the Red Line to commute to the State House, said that riders are frustrated, and the T should ensure it has plans in place to mitigate delays.

“People will accept grudgingly a 20-minute longer commute if that’s all it is. Anything beyond that leads to extreme frustration,” Keenan said. “They will grudgingly plan for it, but nobody’s happy.”

A return to normal service would mean Red Line trains are running about once every four minutes or so during rush hour; they are now running about once every six minutes at peak hours. Those four-minute headways were already too long for the levels of ridership, according to T officials, who have invested hundreds of millions of dollars in a whole new Red Line fleet and signal system upgrades with the goal of reducing those headways to three minutes.

The T doesn’t yet have a grasp on how much the Red Line repairs will cost, but even the limited resumption of service has required a significant increase in staff work.

“I do want to give everyone the assurance that all the resources of the MBTA are being put forward to this recovery effort. We have not only our internal forces but plenty of external contractors working to solve this problem,” MBTA General Manager Steve Poftak said on Friday. “It is not a question of resources. It is a question of extensive damage to equipment that in some cases dates back to when this area was constructed.”

Because the electronic signal system was wiped out, roughly 50 people are required to manually signal and switch the trains running on both the Ashmont and Braintree legs. The crash occurred near the split between the two southern branches of the T’s busiest subway line.

“This level of service will be in place through Labor Day, and then we will have further updates as our recovery process progresses,” Poftak announced from the Red Line platform at JFK/UMass. Trains pulled in and out of the station during the press conference where T officials had arrayed pieces of busted electronic equipment to show the extent of damage to the signal system.

MBTA Deputy General Manger Jeff Gonneville said this box, which was damaged by the June 11 derailment, contains circuit boards that controlled track circuits. (Photo by Andy Metzger)

Poftak told reporters the T is “making every effort to accelerate the recovery of the Red Line,” while ensuring that the work is done safely. The T has moved up its schedule for the overall replacement of the old analog signals around JFK/UMass with new digital signals to next year.

The damage affected 99 track circuits that each control a stretch of track, and as the T repairs those circuits and resumes electronic control over the track area, the number of workers needed to manually signal the trains will be reduced, said Jeff Gonneville, the T’s deputy general manager.

“It is our goal to increase the number of trains per hour by Labor Day, however, as these modules begin to come back online [before then] we’re going to start seeing other small, incremental improvements to the system,” Gonneville said.

The affected track circuits were responsible for areas stretching from Broadway Station to the Tenean Beach area on the Braintree branch, and from JFK to Fields Corner on the Ashmont branch.

Since the day of the crash, Poftak has emphasized that he believes the system is safe, and on Friday he had more data to back up those assertions. The T has completed ultrasonic testing on all of its Type 1 Red Line cars, which is the type that derailed last week, and found no other “systemic issues” with those cars, according to Poftak and Gonneville. The Type 1 are the oldest cars on the Red Line. The T has 74 of such train cars, with 68 in active service.

“Every vehicle that’s in revenue service has been inspected and no defects have been found,” Gonneville said.

The T hasn’t yet determined the cause of the crash, which did injure at least one passenger. According to the Boston Public Health Commission, about an hour after the derailment, one person returned to the scene and was then transported to a local hospital by Boston EMS.

The T has narrowed the focus of the investigation to the vehicle, which began service in 1969, and Gonneville said the agency has been looking at “all pieces of the truck assemblies,” which are located below the passenger area of the vehicles.

After Gov. Charlie Baker took control of the T following the Snowmageddon winter of 2015, T officials and the new Fiscal and Management Control Board prioritized both investing in capital repairs and upgrades to the sprawling network as well as a getting a tighter control on operating expenses, which had previously been on much more of an upward trajectory.

Gonneville said that it is “absolutely not” possible that any reductions in operating expenses contributed in any way to the derailment.

Going forward, Keenan said he hopes there are efforts to mitigate the delays for Red Line passengers, and suggested one possibility could be by supplementing the train service with buses that bring travelers directly to stations to the south of JFK.

“I have been riding it so I know what’s going on,” Keenan said. “I’m as frustrated as everybody else.”