Now I'm confused. From work, it took me to an Amadeus site with aa in the subdomain (which I did think was odd) and I could see economy and business on the direct JFK-CAN flights with AA flight numbers, but the premium economy had no price against it.
Now I'm at home and trying to do the same thing, it's staying on AA.com, offering me Main Cabin for double the price of earlier today, no Prem Econ and business on one of the two flights of the day (July 14, FWIW).
I'll probably start my journey from JFK, but if there's a reason to I can start from BOS. I'll want to get back to BOS in the end anyway.
If I search BOS-CAN it only has 2-stop options, no BOS-JFK-CAN.