pdeut

I was surprised to have stumbled across this today while making a change to a booking I had previously made. Essentially, I was able to "rebook" onto the same flight I was originally on for a reduced price. Naturally, this should only work if the price you originally paid for a leg was higher than the one currently offered. In my case this was a MUC-CDG round trip, originally Jan 5 - Jan 17. I wanted to change the inbound leg to Jan 18, so I started the rebooking process in the AF app. It asked me which (or both) of the two legs I wanted to change, and I selected both as I was curious about the other flights on Jan 5. When the flights for Jan 5 came up, I saw my original flight listed as "-$14". I selected this, and proceeded to pick a flight on Jan 18. Due to timing constraints, I had to pick one that was "+$10", but this still produced a net total of -$4 of a change fee. The rebooking went through, and I was emailed, telling me that my $4 refund was on the way. This is major news if it works across the board, as you could "rebook" yourself onto lower fares on the same flights. Since the trip length changed from 12 to 13 days, I can't imagine that a lower fare was triggered due to MSR. Has anyone else had a similar experience?