I searched on Air Canada for a ticket from PHL (Philadelphia) to ICN (Seoul, South Korea). They offer a ticket with a transit of only 53 minutes in YUL.
Is this transit time possible? What customs would I need to go through in Montreal? Any additional security checks? I am a Permanent Resident of the US, so I do not need a transit visa. But usually, it takes me a bit extra time to clear the US customs.
Are they in the same terminal? (The US arrival and international departure)