Originally Posted by
jamesbondc
...I called US Airways and associate says no changes can be made once the travel begins but in T&C it doesn't say that. They said if you don't fly you lose. ...
Unfortunately, the US agent is correct - once award travel has started on a partner airline, no changes are allowed. Also, US charges the same amount of miles for a One Way as they do for a Roundtrip, so if the outbound has been flown, there's no miles to refund if the return is not flown.
The full T&Cs are found
in the DM membership guide (emphasis mine)
Travel on partner airlines
•Changes to origin, destinations, class of service, award level, dates and times are not permitted once travel has begun.
•If you cancel your award trip, we will not automatically redeposit miles or refund fees.
•One en route stopover per itinerary is permitted for select international travel awards.
•Award travel on Royal Jordanian and Virgin Atlantic must originate from a valid US Airways-operated city.
•Flights operated by a non-partner airline with a partner airline code are not eligible for award travel.
•US Airways is the final authority in choosing the routing and Dividend Miles partner for award travel based on the desired origin and destination.
•US Airways is responsible only for Dividend Miles program awards and does not assume responsibility for partners’ program awards
•Specific Dividend Miles partners and destinations may change with or without notice.
•Around-the-world itineraries must follow one global direction (either eastbound or westbound), and the Atlantic and Pacific must be crossed only once.
Have they made exceptions? Yes, but rarely. Natural disasters, airport closings, etc.