The problems are prepared. This trollathon rules are similar to those of Trollathon 1 and 2. The date and time of the contest (which means the date and time the set will be announced here. I'm currently waiting for the completion of the new leaderboard. In the meantime, do Trollathon 1 and 2 (30 problems) to get yourself familiar with Trollathon.
UPD : The problems will be released around 12pm GMT of 7 April 2014.