It didn't happen to my sister nor a friend. It happened to me.
I was doing the ORD Bonus MRs, 2 in 2 days. The routing was TPA-DFW-ORD-DFW-TPA with the same routing on both days. On the first day the ORD-DFW flight was getting seriously delayed and I knew that I would never make the last TPA flight of the day from DFW and thus I would not make the second day MR.
I called EXP desk and explained the situation. I was routed on a non-stop ORD-TPA, voluntarily, that day. Not only did I get the original routing mileage but it also counted as part of the ORD bonus. I called AAdvantage CS and explained it to them and the agent had no problem adding the ORD-DFW-TPA segments. In fact he left the ORD-TPA segments which caused a problem with the bonus so I had to call again and have them remove that segment. (you can't win them all.....
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