Ai Perception: Not Updating on Patroling Enemy

Hi there!

I am using Ai Perception on an NPC that is patroling and setting different things when he & looses sight of my playercharacter. All works well when my player walks into and out of his sight. However if the NPC moves and looses sight that way, the OnTargetPerception Updated doesn’t fire.
It’s driving me nuts. Is this a bug, am I doing something wrong and is there a way to work around this somehow?