Originally Posted by number_6

The rules changed about a year ago. All BA non-US flights are eligible for AAdvantage miles earning, thus all Canada, Mexico and Carribean flights. YYZ-LHR, YVR-LHR, MEX-LHR, BGI-LHR for example and many more. Also all flights to South America, LHR-EZE-JFK is particularly good alternative to LHR-JFK, albeit taking a day (or week) longer, depending on your proclivities. But also costing quite a bit more money.