Metrolinx contractors continue to work on a long-term project to revitalize train and passenger infrastructure in Union Station.

It opened the new GO Transit York Concourse to provide passengers with better access to and from train platforms and more amenities to enjoy while they’re heading to and from the trains in April 2015.

More than a year ago, Sunday, August 16, it closed GO’s Bay Concourse — the area at the east end of the station along Bay Street — for as long as two years.

The next phase of the project involves refurbishing the steel train shed and then installing a new roof, starting tomorrow, Monday, December 19. To do this work, it’s closing platforms 7 to 10 and the tracks that serve them, meaning it has to find different platforms for trains to serve passengers in the station. That same day, it’s reopening platforms 11 to 13 — which it closed Wednesday, August 10.

Many GO Transit trains operating along these lines leave Union Station from different platforms than usually, starting tomorrow:

• 01 Lakeshore West;
• 31 Kitchener;
• 61 Richmond Hill; and
• 65 Barrie.

Closing platforms 7 to 10 does not affect GO train service along the 09 Lakeshore East, 21 Milton and 71 Stouffville lines.

Here’s how you can get to various GO train platforms at Union Station, starting Monday, December 19: