Universal Distribution has now added some description of the event on their site:
The Tomes of Power Storyline contains an epic quest for three mysterious and powerful lost tomes. At the inception of this saga, the Compass of Lost Treasures has revealed that a powerful tome is hidden within an ancient tomb filled with treasure chests. Legions of creatures have flocked to the tomb and must battle for control of the tome.
After the first bout of looting and fighting, the compass guides the rival legions to a long forgotten battlefield. The battlefield contains magic ballistae scattered throughout the plain that are still active. As the players battle for control of the second tome, they may gain control of the magic ballistae and use them to blast their opponents from a distance. In the epic conclusion of this storyline, the heroes are guided to the final tome, which lies buried in the center of a large valley.
Each legion has amassed a mighty force to fight for the last tome. Will your legion be able to overcome the trials at hand and collect all three tomes to gain inconceivable power?
And releases are set to march, april and may next year.