Next time the a/c will have a mechanical
and be delayed 45 minutes ,have another delay and finally be on their way.You were told the truth.
30 late pax arriving YUL could have connected somewhere from Europe ,being delayed for days.So many what ifs.
I have been delayed many times YYZ/BGI due to cnx pax be it weather in YYZ or YUL/YOW.
Goes with the holiday season.If in a hurry,don't go shopping