I once did EWR-CVG-ATL-FNT (i know stupid routing but it was dirt cheap). Was upgraded ATL-FNT. Had problems with the ATL-FNT segment since checking in at EWR. One agent said that it was because my flights were too far apart, which wasn't true. I couldn't get my boarding pass for ATL-FNT. Anyways, IRROP happened and I was able to change to ATL-DTW (yay!), and I was rebooked in F fare. Was very happy to see that 100% MQM bonus. And no, they did not audit it