A Chronomancer may interrupt during both his and his opponen'ts turn. If he interrupts an enemy unit, he must finish all his actions before the enemy unit continues.
He can interrupt at any time during any activation, but cannot interrupt involuntary movements or actions. He can interrupt models coming off Wait, and Waiting models cannot come off Wait to act against the Chronomancer.
They cannot interrupt an Enlightened, or another Chronomancer.