If the lake level is coming up slowly they will move out to the first break unless the water is coming up fast and then they will move out to a major breakline (15-20ft)or if the channel is close they will move to it until the lake level stops rising. Then if the level stabilizes for a short time they will move way shallow into the new shallows. If it is during the spawn they won't move into the new shallows to spawn but will spawn in deeper water. This is what I have noticed in the Midwest but it may be different in the South, but fish are fish and will do the same most places. EB