I suspect a new hatch of shad. That means you'll find fish that won't bite because all lures are too big, and you have to keep searching and trying til you find fish feeding on the bigger, older shad. I haven't had a chance to spend that much time on the lake since this started, so this is just my theory until I can get out and prove it.
Interesting theory Dennis. I noticed a million small shad around my dock this weekend. Then went out fishing Sunday afternoon. Marked a huge school of fish. I was bouncing my slabs off their heads - literally. No bites. Switched to trolling a #12 pet (about the size of the shad) behind a hellbender and caught fish every time. Not sure if this is enough empirical evidence to prove your theory or not!
I hate trolling. Maybe this is the year that I will learn your Mepps Method.