Okay, I PM'd a bunch of people and from their responses it looks like finding the perfect Sunday in June is going to be hard to pin down.
M.E. and I did "secret girl things" behind the scenes and decided to do a scouting ride of this route on Sunday, June 17th (Father's Day). I will schedule the BF group ride for later in the summer or fall, which will be perfect since other areas around So Cal, unlike PV, will become unbearably hot. Plus, with Mary becoming familiar with the route, I can have more ride support/lost people finders.
We will still be open to people joining in on the 17th!