I'm not sure if this expanded relationship has taken effect yet, but I just noticed that UA1910 is no longer DEN-YVR. For as long as I can remember, this was the UA-operated evening flight to YVR. Instead, AC is now operating the evening flight. I could have sworn UA also operated an afternoon/early evening IAH-YVR flight. Now, it's only one daily and it's in the morning. I believe AC is operating the later flight.