M_Boats: M15 and M17 on highway 101 yesterday

So, I'm driving out to Lake Sonoma yesterday, and I get really close to my turn on Canyon near Geyserville, and right in front of me is another M15 being towed north! I couldn't see the name of the boat, and I thought they might turn also onto Canyon to go sailing. But they continued north. Ken Wheeler told me he saw that boat, and an M17 also going north. Who was this? Anybody on the list? You just don't see too many of these around here! Daniel