I'm seeing contradictory info on this one. I'm planning a trip through LHR from AUS in January. Whether we take the BA nonstop from AUS or connect via DFW on AA, we arrive in T3 and our onward connection on BA is in T5 (GVA). I am inclined toward the DFW connection if we can avoid re-clearing security. I did a T3-T3 connection last month from DFW and loved it, but how does this work with the T3-T5 bus transfer? Do they run special busses to T5 for the DFW connectors or are you intercepted at T5 flight connections and routed directly into departures?