Hi Jim, I think the big difference came from the old format with WKA and the new format. Before, they ran qualifying, prefinal and final each day. Most of the time, that added up to be less then the laps provided by USPKS. Now, they are qualifying, Heat 1, Heat 2, Prefinal and Final.
Talking with WKA President John Ferris, the new format has been a big hit with racers.