I was booked in a full fare J seat from CDG-DTW. Had chosen window/aisle seat in Delta One. I was not Elite, but, hey it WAS a fully refundable J seat with a hefty price tag. A week later I got the dreaded "Seat Duplication" email. Booted me to the center section, although an aisle seat. No other single window/aisle seats were left.

I figured a VIP or Diamond wanted my seat, so out I went.

Have flown plenty of J trips since. None on Delta. That stunt cost them my business. To be fair, I had had other issues with Delta. That was the straw that....