If it's as crowded as it was last year when it re-opens for the holidays, don't go first thing in the morning. It's great if you want to meet Olaf, but the 3 times I went last winter/spring, the actual attraction was having "technical difficulties" and we got to meet Olaf, but no snowfest. Best bet I'd think is to stick to the stuff in the Hollywood area that's close to it and keep an eye out. When it's clearly open, head over.