Sometimes big companies will buy out the park for the evening for events. If I remember correctly there was one of these events when I was there in September during that time last year. Also companies will set up conventions at the Resorts that will cause limited availability at the Resorts. September seems to be a popular time for conventions at the Resorts.
I saw a lot of the convention attendees also going to
HHN during the evening last year. It would be nice to work for a company that provides convention events thst close off a park in the evening for your enjoyment as well as provides tickets to HHN.
This year it looks like HHN will be a very busy event too. I have never seen the Premier Resorts selling out like this.