Yes, it will be unless the rules state they cannot be upgraded, usually e-fares or web fares sometimes originating in Europe (there were some ex-LHR and CDG fares that were non-upgradeable a while back).

To upgrade using miles, you must purchase a Y, B, M or H fare and for the rest, you can upgrade using a SWU except for things like special T fares. Q fares are upgradeable, even lower ones like W and V.

Hope that helps!



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When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return.

- Leonardo da Vinci