I've flown into Canada at YYZ quite a bit in the past, and normally go through Canadian customs there after exiting the plane. Easy-peasy. All the times I've flown into Canada from the US have been directly to my final destination, which is also a port of entry.
But this time, I'm planning a trip that will take me through YTZ (Billy Bishop) instead, with a connecting flight to Halifax (YHZ). Will I be able to clear customs at YTZ or will I do that at YHZ?
The flights I'm looking at have a relatively short layover time, so I'm a little concerned about being able to make the connection if I have to go through customs first.