You might want to try moving after dark. From the sounds of it, you are setting up on a drop off at dusk? If I were in your shoes, I would go even shallower with the tip ups once nightfall sets in, maybe try 2-3 ft of water tight to shore. Those walleyes could be moving from the depths during the day to the skinny water tighter to shore at night and cruising for baitfish. They gotta go somewhere, and sitting in your "dusk spot" all night certainly doesn't sound like it's producing after dusk, so might as well try something different, right?
