The balancing act between providing service to late-night riders and doing preventative maintenance is getting a deeper look after the D.C. members of the Metro board demanded a return to 3 a.m. weekend and midnight weeknight closures.

It appeared the board was heading for a showdown and a vote on the issue at Thursday’s meeting. Instead, the board asked Metro staff to begin to look for other hours to do preventative maintenance. They’ll bring that report back in January or February.

But it will likely be difficult to find other hours in the day that won’t disrupt other passengers, Metro staff says.

“I do want to get more service out there,” said General Manager Paul Wiedefeld, adding that Metro will take a look at the hours and at trying to do the work better or quicker. “But we’re not going to do that at the expense of keeping the system safe.”

Earlier this week, the D.C. representatives on the board pushed a return to 3 a.m. closing on weekends and midnight on weekdays. They were later joined by members from the Maryland General Assembly and local governments.

Metro board chair Jack Evans, who also represents Ward 2 on the D.C. Council, said residents have been patient, and that people who depend on Metro to get to or from work at night or go out at night deserve to have that service back.

But the transit agency fears that expanding service hours will create another backlog of work, similar to the one that produced the year of SafeTrack surges in 2016 and 2017. WMATA uses the overnight hours when trains are off the track to check electric cable insulation, track inspection, and do other maintenance. That work can only be done with power is shut off, meaning that extending service hours reduces the amount of time available to work on the track. Metro argues that there are other ways for late night riders to get around, like buses and ride-hailing services.

Wiedefeld said there is no definitive date by which he sees late night service returning.

“We’re only 18 months into this (preventative maintenance program),” Wiedefeld said. “The bad old days are not far behind us… we still have work to do. When we rolled this out, we did not put a time limit on this because we didn’t know what we had (out on the system) and we’re just starting to find that out.”

Evans said he wants to examine operating hour options that were on the table two years ago when late night service was cut. They include possible smaller midday shutdowns or starting later on Sunday. But, he added, he doesn’t know where Metro will find the hours.

“No matter when we do, it is inconvenient,” Evans said. “Closing early at night is inconvenient, closing whole lines is inconvenient…There’s no easy solution here… we inherited a system that was neglected for 15 years.”

Metro board member Christian Dorsey, who represents the Arlington area, said “SafeTrack light” shutdowns, in which whole sections of lines were closed for maintenance, aren’t a viable option either.  “Constituents that want late night hours would hate that alternative even more,” he said.

Maryland board member Michael Goldman stressed that safety and reliability should take precedent over expanded hours.

Laura Mason, who is in charge of rail infrastructure and maintenance at Metro, showed data that on-time performance and rider satisfaction is increasing in correlation with the additional late night work.

Mason said the system has shifted from reactive to proactive work thanks to the extra hours, and suggested the board protect those hours. WMATA had 33 weekly hours of maintenance time from 1999 to 2016. That number has increased to 41 hours a week currently. The data also shows that track incidents are down 86 percent and emergency work is down 72 percent since 2017.

The transit agency cut Metrorail hours in 2016, moving the system’s closing time from midnight to 11:30 p.m. on weekdays and 3 a.m. to 1 a.m. on weekends.

This story originally appeared on WAMU.