Are all the vendors normally set up and selling by Wednesday morning? I've never been on that day. I'm checking the weather and so far, Wednesday looks the best.
The "load-in" is on Tuesday. By Wednesday morning, essentially all sellers are open for business and many I feel would argue that it is probably the best day to walk the fields provided the weather is good.
You just about need three days to cover it all. I almost did last year, but Friday afternoon rain called a halt.