The preview for episode 1 of the latest creation from Key has already been released.
Just a reminder: this new series is being worked by Aniplex (Sword Art Online, Anohana, Durarara!!, Fate/Zero) and P.A. Works (True Tears, Angel Beats!) while of course, Charlotte VN itself was written by the master Jun Maeda. It is expected to start on July 4.