Following an announcement in March that it would begin testing automatic train door operation, Metro is finally rolling out the practice on the Red Line starting July 7.

“Metrorail customers on the Red Line may notice a quicker commute starting July 7, as Metro resumes use of trains’ automatic door-opening feature,” said the Washington Metro Area Transit Authority in a press release on Wednesday.

Metro discontinued automatic door opening years ago because of what the agency has called “reliability problems and overriding safety concerns.” In 2008, there were several instances of doors opening automatically on the wrong side of the platform, and Metro began instructing train operators to open the doors manually pending necessary updates to the automatic system that would prevent this from happening (train operators have always closed the doors manually). This was back when the whole of WMATA’s system was operated automatically; a train operator was present on every train to oversee the system, but the trains drove themselves via a system called Automatic Train Operation, or ATO.

Then, in 2009, there was the fatal crash at Fort Totten, when a signaling system failed to detect a train on the platform, and one train crashed into another from behind. Nine people were killed, including a train operator. ATO was not directly at fault in the incident, according to a National Transportation Safety Board report, but WMATA disabled the system entirely afterward and switched to manual control. That included the doors.

But in the intervening years, train operators have sometimes made the same mistakes as glitchy 2008 machines. In its March testing announcement, Metro cited several instances in which operators accidentally opened doors on the wrong side of the train. To prevent this from happening, the agency instituted new rules years ago requiring operators to wait several seconds after stopping before they open the doors.

The plan is for automatic doors—this time, presumably, safer and sans glitches—to open immediately once the train is stopped at the platform, saving you a few seconds at each stop.

Metro announced Wednesday that it had trained hundreds of operators and “tested and tuned” the system in advance of the Red Line rollout. A spokesperson told DCist that system testing continues, and the agency hopes to introduce automatic doors on the other lines by the end of this year.

It was once assumed that reinstituting automatic doors was a precursor to a move back to ATO on the entire system. In fact, Metro General Manager Paul Wiedefeld has said as much in 2018, announcing that the system would move back to ATO by the end of this year. “Just looking at system performance, the system is designed to operate in ATO and it runs better in ATO,” Metro spokesman Dan Stessel told the Washington Post last year.

But the agency has broken that promise before (including as recently as 2017), and it seems to be happening again. NBC Washington reported on Wednesday that there were no immediate plans to return the system to ATO. The agency told the outlet that ATO “is not a priority” for Metro at the moment.

Gaspard Le Dem contributed reporting.