I think you mean Saturday April 24, 21:00 GMT equals Sunday April 25, 9 AM your time. Of course we can let the festivities begin at Saturday morning your time, which would be Friday afternoon in the USA, late evening in Europe. Besides I'm leaning more towards calling it an event than a competition, but of course deadlines are good to set.
Not sure if all participants have signed up to the forum, or some will post their results on respective web sites and elsewhere post links. Many may participate without the meaning to get evaluated, but we'll see about the turn out.