Yes, it can be fixed. You can emulate this problem with a porous kitchen sponge, by only getting half of the sponge wet and letting it dry. The cellular area that is wet expands, but when it dries it does not match the exact same compactness as the area that remained dry. It's not less or more necessarily, just different. If you then soak the whole sponge and let it dry, everything is consistent. The same is true with shoe leather. When you discover a ridge like this take a damp sea sponge (soft sponge) and soak the surface of the entire shoe (not dripping wet, but damp to the touch). Let the shoes dry overnight, then condition them with leather conditioner (to add the lost oils back in), and the shoes should be fine. If salt was absorbed when initially exposed, then you may also want to use a little saddle soap, when getting the shoes damp with a sponge, to allow the sulfides to flush out the salts. Be sure to rinse out the saddle soap with a clean damp sponge before allowing to dry.