I think some of you are being too harsh on AC and GTA. On Tuesday night I was traveling from YOW-YYZ-GRU-GIG on AC and I made it albeit with a lot of delays.
First when my delayed AC flight arrived in YYZ, there was too much snow for the plane to get to the gate so we waited for a plow. This could have been avoided with better planning. But when we got to the gate, it was frozen and could not move over--- further it developed an electrical short which means the fire trucks were called in. An hour later we are moved to another gate, also frozen and would not move over to the door of our 319. Eventually GTA got that fixed. 3 hr delay in total.
Then I went to ML in international side. YYZ-GRU was at first one time, then delay one, delay two, delay three but eventually left around 2am++ which means I missed my GRU-GIG connection and had to wait a couple of more hours for the 18:10 JJ flight. As you may know there are very few JJ flights between GRU and GIG.
I admire pilots and all crew willing to work in these very difficult conditions. The conditions out side for ground crew were miserable and they had to seek warmth after a bit of exposure. GTA should have and perhaps did call in all extra staff. I do not know but they should have.
T1 was more like a youth hostel with people sleeping everywhere.
I also think AC should have sent a notice and a gesture of good will to its passengers. When I experienced similar problems at YUL on flight to GVA in mid December, I was sent a 25% discount for a future flight.
I received nothing and had to buy terribly expensive food and drink at YYZ as ML promptly shut down at 11:30pm. Conceirges were invisible.