Not sure if this is useful info for anyone, but I had an Aeroplan reward booking, BKK > HKG > YVR > YYZ (travel in Mar 2023). I received an email from AC saying there was a flight change of 15 mins on the HKG departure. When I clicked on the link to verify, the next page said "You have been re-accommodated on the following flight: HKG > YVR > YYZ, and showing the 15 minute difference.

But lower in the page it also gave me some alternate flight options and "All changes are free of charge". One of the options was a non-stop Cathay flight CX826 HKG > YYZ, as well as options to connect through TPE and then non-stop TPE > YYZ.

Looked like a no-brainer. I chose the non-stop CX826 flight option.