Mine was changed from
YOW-YUL-LAX (AC)-SYD (united)
SYD-BKK-HKG (TG) (STOP)
HKG-KIX (AIr India) (STOP)
KIX-PVG-YYZ-YOW (AIR CANADA)
TO KIX - PEK (NH) - YUL- YOW (AIR CHINA)
And it saved me $500 bucks in taxes. It brought it down to $350 instead of $850. So that AC YQ is really hitting hard when it is coming back from PEK cause it counts from SYD as mentioned above.