I'd be very interested in joining, I'm just waiting to hear whether a prior arrangement with the kids on Saturday is going ahead or not. I hope I can make it - it would be my first ride in company (apart from short pootles en-famille, that is)
The route looks interesting - I've never been out to Mersea Island, but one of my recent loops has taken me on a bit of that route round Abberton Reservoir, and other rides have taken in the lanes round Braxted. It looks like I've always ridden them in the opposite direction to that route though, so it would be a new perspective on a few familiar-ish areas (I say familiar-ish since I only normally "see" them in darkness anyway...)
Cheers,
Mark