Thanks
zaibii . Was able to book YYZ-CDG-LHR, LHR-SEA-YVR on AF/DL for $1569 via AMEX IAP, a bit cheaper than the $1620 I was pulling on GF/ITA.
Could have done AF or VS for a bit less, but I wanted to fly DL 767-400 on the return as the AF options out of LHR were 6:25am departure, and the VS options were the old upper class.