DP: I recently had two one-way flights booked on the same day, from different airports (100+ miles apart) in the broad LA area to AUS. I thought that was OK to do so I could choose the best one depending on circumstances and cancel the other. Now that I'm reading this thread, I was obviously wrong. The most recent flight among the two was cancelled (almost exactly 24 hours after booking) and I received flight credit (it had originally been booked with flight credit).