Our "Local" contests (at Huntersville, NC) are run on 4 circles. One grass, two paved, and one that is added to the end of the R/C runway. Beginners on grass, Adv, and Expert on the two paved "dedicated" circles, and the Int. on the lower end of the runway. It has been sorta "L" shaped to get in a fully paved area. OTS usually is on the grass, Classic on the paved and Profile on the runway.
One of the "dedicated" circles is used for Scale and Racing on Saturday while OTS, Classic and Profile are being flown.
All classes are going on at the same time on Sunday.
I went to Flushing Meadows back in '97 for the final contest that Joe Ortiz put on there. ALL the classes were flown on ONE DAY! And it was not a problem. Plenty of flyers, too!