Originally Posted by
gateguard0
If you go from Canada to Hawaii, you may stop enroute. You may fly on AC/UA/US.
If you go from Canada to continental USA, you may stop enroute only if you fly on AC and/or US. You may not stopover (separate from the final destination) if you have any component of the itinerary on UA.
Once, when I booked an itinerary with the SE Aeroplan agent, they got mixed up between the 2 sets of rules. The agent though that the one stopover restriction with UA also applied if the final destination was Hawaii; I had to clear her up by asking her to read the rules on her computer.