Never flown Porter before, but I need to make a SEA-YYZ trip in a few months, so wanted to take the opportunity to try out Porter via a connecting flight through YVR. I further wanted to book the YVR-YYZ leg in Porter Reserve, which I understand translates to Premium on the AS website. But when attempting to book a one-way SEA-YYZ flight on the AS website, it seems that for any connecting flight on Porter, the Premium option is always greyed out. Only the Main option is ever available. I eventually got it to work by booking it as a multi-city itinerary (with both legs occurring on the same day) rather than a one-way, but it sure seems like a non-obvious workaround that might be missed by some folks.

So in the end, I ended up booking a multi-city same-day itinerary on the AS website that booked into fare class V for the SEA-YVR leg on AS metal, and into fare class U for the YVR-YYZ leg on Porter metal. The YVR-YYZ leg also has a Porter flight number rather than an AS codeshare (and I had to use the Porter website in order to select seats for that leg). Does this mean I'm likely going to run into issues earning AS EQM/RDM for the YVR-YYZ leg? Also, I'll be travelling with checkin luggage. But I shouldn't have any issues at SEA checking the bag all the way through to YYZ, right? Last thing I'd want to have to do is pick the bag up landside at YVR and then check it back in and clear security again.