Originally Posted by FlyerGoldII

I have decided to go to Boston from Delhi via YYZ - then later that day, take the direct BOS-YOW flight.

Questions on transit in YYZ:

a) I do not have to pick up luggage at YYZ?
b) Will I get OSS, or not? If I do get it, what is the practical effect?
c) Exiting the plane - what is the route I take from AC arrivals gate to Canadian customs/ Immigration to US pre-clearance security and customs/immgration?
d) Do I go to the main Canadian customs hall, or not?
e) My wife and I have nexus. Which steps of our transit can we use nexus; which of our steps can we not use it?