At SCY Nationals, is sixth event usually allowed?

Is the sixth event usually allowed for SC Nationals or is it usually dropped? I entered SCY Nationals in 2008 and recall that the sixth event was allowed. When I entered LC Nationals this past summer, I noticed that the sixth event was dropped. The reason I am wondering is that I have registered for Nationals and now regret having chosen one of my events as the sixth event. I would like to change which event I would like designated as the sixth event, but wonder if I can do so after already registering. If the sixth event is routinely allowed at SC Nats, I just won't worry about it.