It's not certain what the cue was, or if there was any tell that gave it away, but suddenly she's moving. Quickly and as quietly as she can so as to be in a better vantage for an attack when she was finally picked up on sensors. The baton still dark before flashing on as she goes for the first and hopefully only hit needed to take him down.

Trajectory and force is right on at the moment, but if he moves in a way she hadn't planned for he could slip past her in those precious few seconds as she brings the unfamiliar weapon back around for another strike.