The airline says the move is in resonse to record fuel prices. The new policy applies to all flights booked on or after march first.
It will no longer offer a minimum of 500 miles for every flight. It will now award them based on miles actually flown. Passengers who redeem miles for flights booked online less than two weeks in advance will be charged a $50 fee. A $75 fee will apply if those flights are booked through US Airways reservations.