Being a expert in my own eyes on Crappie and their spawning habits causes me to have a different theory. Temps were warmer than normal this year. This made the temps in the upper part of the water column be much warmer. When I was catching fish on the local lakes a couple weeks ago, the surface temps were above 60 degs however the fish 10 feet deep would come out of the water ice cold. Since it is now time for the spawn, the fish are making their way to the shallow water which is now much warmer than the optimal spawning temperature, so the fish will back out into slightly deeper water to have the comfortable temps while spawning. In other words. Same time of the years as every year, but not in the same places.

I will admit, I have never caught a crappie during the spawn so I may not be the expert I think I am.