In an email to players, the Arena of Fate team announced that the game would be returning for a testing session this month.
The test will run from 5 to 9pm CEST on May 31. The developers stated:
The AoF developers have been working hard to improve the game, and in the process, they rewrote the game’s backend. Now we need to test it, and we need your help. Play against the developers, check out new features, and help us stress test the system as you pit heroes of history against heroes of myth on the battlefield.
Further details are available in the AoF forum.