A day after ground was symbolically broken on Montreal’s upcoming REM light rail system, it’s becoming apparent the coming years of construction will hold several headaches for the users of the city’s existing commuter rail lines.

While the RTM announced that work transitioning some of its existing lines to accommodate REM trains will cancel some trains existing trains for over a year, on Friday La Presse reported the work will also cause the closure of the Mount-Royal Tunnel.

Those taking the Deux-Montagnes train into Montreal will have to get off at the De Ruisseau station and board a shuttle bus that will take them to the Sauve station on the metro’s already crowded Orange Line.

Pierrefonds-Roxboro Mayor Jim Beis said he was only made aware of the situation on Friday.

“What we’ve asked from the agency is they hold public meetings in my community, which was done a couple of weeks ago,” he said. “(They need to) advise and inform the public on what the next steps will be and not to be faced with a decision that will come into force relatively quickly and not allow for the public to act accordingly.”

Part of the REM line will begin running in 2021, with the full system scheduled for completion in 2024.

On Thursday, it was announced that trains on the Mascouche line will be cancelled on Friday nights while the Deux-Montagnes line will also see cancellations. Both lines will be closed entirely on the weekends.

All closures those closures will go into effect on April 27 and will last until next fall at the soonest.