Tom is correct, the time needed to attend an Internats is just not there now. The Charleston club hosted the last one in June 2012 and due to the time commitment the attendance was about 130 racers. Not really enough to justify the cost and time needed. The host club has to provide awards for each of the heat racing, SAW time trials and the oval time trials and then the final awards. That is a huge financial outlay for the host club. If you do want trial records to be eligible for national records, then a course survey is needed and that is $400-1,000 additional. Only time will tell if the Internats format will continue in the future.
The Charleston club is hosting the 2015 Nitro Nationals in late June and will be the heat racing national championship format. The race will be open for registration next week.