Couple of useful tips:-
You can generally only count the minimum distance of a calendar event, not the stated routesheet/on-the-road distance.
For a 104km event this means you can, usually, only use the completed calendar event Brevet card to claim 100km for that segment.
this is sort of true; many just over 100km events can actually be cut short to even slightly less (-2%?) than 100 if you want to use 3 lane A roads etc but it's a good rule of thumb to allow the exact number of km and add the DIY bit to it (Andy Uttley will know the shortest possible distance of the calendar event assuming it's on his Manor) remember too that a potentially underdistance 0 AUK point 100 is more likely to be allowed through than as part of a 200
If your preferred route to the start is a lot less than the direct busy road you can either add another checkpoint en route buying a Mars bar etc as proof of passage; this will buy you more time as it will then be a minimum distance so you will be allowed more time pro rata, or else overshoot on the way home and go to another town n km the other side (eg for me on the Hailsham events going back the laney way via Horley even though the shortest route would take me there via my house).
Remember that the 100km event is unlikely to be at Randonneur speed so you will have less time to complete the DIY bit if you use the full time allowance for the 100 (only likely to be a problem if it's uber-hilly which 10 bridges over the Thames is unlikely to be). This works in your favour when extending a 200+ 15kph minimum ride as you have more time to complete the DIY bit in order to give an overall average of 14.3 minimum.
Give my regards to Mick the organiser not seen him for a few years
