"aving said the above, I would not have booked on a flight from YUL that allows only a 1hr 1min connection time at YYZ- especially not in the winter."
Likewise. I have sympathy for the OP, but I would NEVER book a flight with an international connection with that small a window. I'd provide 3-4 hours at a minimum, and if there was any weather, I'd move the original flight up.
In fact, I had YYZ-YUL-BRU -- with a 3 hour connection. Got to YYZ, things are a mess, and I had them move up YYZ-YUL by a few hours.
Otherwise, you are playing with fire.