True...but it's due to the nature of the edge dressing--being more like paint than dye. So it will continue to happen. and as it does it exposes the underlying leather to moisture.
As an alternative, sand these edges lightly and uniformly with a fine sandpaper (240 +/-) to remove loose dressing and then put a dk. brn cream on the edges--it's a more natural look that won't flake off.