They don't spend much time promoting the rally because it's always "sold out" a year in advance.
Your information above is from 2014.
The rally this year is May 15-17, 2015.
Many of the trailer arrive early, and some leave later.
The "open house day" is Saturday.
The open house day is crazy, as they advertise it on TV, Radio, and the local newspaper. The number of people is almost "too much". It's great talking with people "truly interested" in vintage trailers, but most of the Saturday people are general public with tons of kids, wanting a free entertainment day at the beach. The whole advertised open house thing is wearing on the regular's.
Stop by, say hi, we are camped just inside the main gate, first row on the right every year.