From reading this thread, the take away from the current status quo I'm seeing is, for the 2 or 3 events that are competitions (not chasing rankings), trust no official, there may not be any "source of truth" that you can go to in advance, and get there early and figure it out for yourself. Kind of crazy for something at this level. I think this can be fixed, and not just for newcomers!
Implementing an optimistic no-earlier-than schedule, along with a, in the tournament announcement, place (and lead time) identified for posting any and all schedule and lake changes (like the USAWaterski event information site, which could be consistent across the country?) could make planning a whole lot easier for the loc, volunteers and competitors, and reduce the issues that arise.
FWIW, I do believe that if you're skiing for placement you have to ski in your assigned running order as running out of order may grant you an advantage.