Were you near the family area? I think ours went off about 2am, although I don't think most people went to bed on the Friday night lol
I love JAE, probably one of my favorite shows. Aswell as seeing the cars and other events going on, you get to have a proper club get together, we have members come over from other countries to join us where we wouldn't normally meet them at other shows. The lack of traders has mainly been because of the weather, quite a lot booked last year but a lot didn't turn up because it rained the week before, even though the show itself had good weather apart from a shower.
They usually release the new dates around January time (although the last couple of years they've tried to keep it the same weekend) as the earlier its sorted the better plot you get (although the clubs for the year before usually get "grandfather" rights over the plot they had previously.