Stop us if you’ve heard this one before: the federal government said Denver’s A Line, the train that runs from downtown to the airport, no longer needs guards manning its crossing gates.

The Federal Railroad Administration allowed the Regional Transportation District, which runs the A Line, to remove the flaggers at noon Friday, RTD told Next. The flaggers at the one crossing along the B Line, which runs from downtown to Westminster, were also cleared.

Guards were originally removed from all A Line crossings in June, but regulators mandated that they return to three crossings, at York, Clayton and Steele, two months later. RTD thought a software problem observed on the G Line, the years-delayed train that will eventually run to Arvada and Wheat Ridge, could be a cause for problems at those three A Line crossings, as well. RTD says that bug has been corrected.

Flaggers will remain at all gates along the G Line; the train is only allowed to operate in a testing phase until a separate, more widespread problem with the timing of crossing gates has been corrected. RTD submitted a plan to the FRA last week that details how it will fix those concerns.

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In a news release late Friday, RTD said its general manager, Dave Genoa, met with the FRA in Washington, D.C. to discuss that plan on Thursday. Per RTD, the FRA was satisfied with the strategy, but they want some additional details that RTD and Denver Transit Partners, the trains’ contractor, have agreed to provide.

According to the release, DTP is at work on adjusting the software. Federal and state regulators will have to approve any changes before the G Line can begin running.