If it is, I'm also wondering if you have a light leak in a body back or magazine light trap. Are you loading the film into the camera in subdued or bright light? I'm thinking it looks a lot like light leak fogging.
In my experience, unfixed strips refixed usually obliterate the image beneath them leaving a clear uneven line of no image. Same with uneven or incorrect levels of developer. Just for the hell of it, I'd check for leaks in your camera and film mag if you're using one. That might turn up some problem causing this too.