IHRA no longer has true national events. Some ProAm divisionals have been incorporated into their national events with enhanced contingencies and running the finals with the Pros in front of spectators. They're still divisional points races, but fun, and it's nice to run most of the program earlier in the day without being at the mercy of Pro show schedule and oil-downs. No word if the Sportsman portion will be changed in any way.
Go to
http://www.ihra.com/ and click on "PROGRAMS" for a list and more details.