Not that the actual partner miles earned mean much toward earning MVP anymore, but had a question on booking flights and earning mileage. I am booking a flight to LHR on AA, but noticed one of the return flight options is operated by BA and on an A380. Because I am buying the flight through AA, even though both AA and BA are partners with Alaska, I've been told that I wouldn't get any mileage credit for the flight on BA metal - because I booked through AA. Is that really true?

So basically, the one way trip is worth only 1300 miles and really doesn't matter too much - it must come down to just flying a 777 or A380 instead. If i book the AA itinerary with the BA operated flight, those miles I don't earn?

Thanks.