As a matter of interest ...
How hilly
was the original hillier 2016 route? I prefer the look of it to the flatter route
and the less hilly 2017 route. I may very well be busy on May 13th (it is a good friend's birthday and there may be a do on) but if not, I fancy coming along and having a go at the 2016 version. (If I can't make it on the day, I might do it solo or with one or two others on an alternate date.)
I wouldn't normally ask about hills because I like them and am well used to them, but that route looks like a prime candidate for my singlespeed bike. I can manage long hills at 3-4% on it and short stretches of 7-8%. It doesn't look like there would be anything worse than that?
Oh, and my other question ... would speeds generally be less than 23 mph and preferably no more than 20 mph? I can do 18-20 mph comfortably on the singlespeed's gear, but 23 mph or above requires too high a cadence for me to sustain for long.