Originally Posted by
sfo3388
2. If you transfer in YYZ to SEA, your lounge is in terminal serving US-bound flights. Not necessarily better than Polaris lounge.
Just to build on this point further, even on the outbound segments where one would have access to the International terminal, partner issued reward tickets (and Aeroplan issued Business Lowest reward tickets) do not have access to the AC Signature Lounge. Not an issue with cash tickets but worth flagging anyways.