That plan met my competitive streak, even though it was Not A Race, so I found myself zooming along with various small groups of riders, and only made one brief stop to remove my rain jacket. Ended up doing 98km at an average of 30.8km/h, which is quite reasonable indeed.
It's probably been 15 years since I've cycled that far with no rest breaks, and that's probably the fastest I've gone on a ride of that length since some time in the very early 90s, when I was still competing in cycle racing of various sorts. Goes to show what riding to work about three days a week since June has been doing for me.
It's still possible to sponsor me (proceeds to The Smith Family, helping disadvantaged children) here.
And ... I think I'm going to enter the 210km event next year, to "celebrate" turning 40. Or something. That could be a whole new challenge, I was pretty confident that I could do 100km, but I've never done more than 150km in a day before. Some training may be required :-)