I think I passed disturbed-az going up the 101 (I was heading to a dr appt, after going home early). Looked like his car, tinted license plate frame. He got behind me and nearly caught up, but traffic conspired against us. I waved out of my sunroof. And possibly flashed hazards. I think.
And if it wasn't him, I spotteded a DGM/black newer hatch.