I was wondering what freq's aircraft call into when they cross from gander center into Montreal center airspace near YMK (wasbush) and YZV (Sept Iles).
From the Wabush (YWK) area it would be from Gander to Montreal on 119.400, and from the Sept Iles (YZV) area (actually covered by Moncton Center) it would be to Montreal on either 133.025 or 123.925 (on the more southern routes).
During the day 119.400 is usually combined with the frequencies monitored on the LiveATC "CYFB Montreal Center" feed, and 133.025 is usually combined with the frequencies monitored on the LiveATC "CZUL ACC (Noranda Sector)" feed. On the overnight both areas are combined so you can hear them on either feed. You will hear the controller and the aircraft too if the cross-coupling is turned on.
123.925 is covered on the LiveATC "CZUL Center (Montreal)" feed.
JS