Long version:
Well the advice was sound!
At 5 am the car park was frozen and I was very undecided on whether to continue but left just before 6 am after much frozen fingered pfaffage with mudguards and GPS. The A44/436 was quiet and off the gritted top still frozen, but it was the right choice into Stow, where I made my second error in not actually drinking my coffee.
The roads into Newent whilst wet were ok and it felt good to have made the first crossing of the river. At the control I bought just a sandwich (e3), as my water bottle was still full!
Onwards and into the forest of Dean, which was wet and still had frozen sludge in places so care was needed on the few descents amongst the many many hills. My plan had been to cycle through to Chepstow and eat there, but I spotted a Fish & Chip shop at the top of the long hill up to Bream where I stopped and enjoyed hot chips with peas then I turned down their kind offer to refill my all but frozen bidon (e4) which was stiill 3/4 full! Nearing Chepstow and within sight of the bridge the sleet started and I was getting colder and wetter, at this point I was aiming for the services on the east side to refuel and rest as I was still in time but could feel my energy dropping quickly; the hill into the centre of Chepstow became a bigger problem than I expected, and the haul over the Severn bridge which I had been looking forward too only offered driving sleet and a stiff side wind. At this point I knew it was time to consider options. At Severn services I finally bought a drink, but the wrong one (e5), drinking half I threw away the water I'd been carrying from Oxford and decanted the energy drink but within 5 minutes of leaving I knew it was a critical error as all I now had to drink was making feel increasingly unwell.
Knowing the next control was still +40km away I made the call that I knew was threatening as I crossed the bridge and rang for a lift to be waiting for me in Malmsbury. Cresting the hill up to the Somerset monument I knew it was the right option as my speed had dropped and my legs were not recovering in between hills, I crawled into Control 4 (Malmsbury) as it got dark, my Coop receipt showing 6 minutes in hand. In the town square sheltering under the market cross and waiting for a warm car I watched others making their own brave decisions.
Error 1. Rationing how much chilled water I was sipping to prevent stomach cramps I completely failed to recognise how little I was actually drinking. Despite all my planning and then concentrating in the saddle on tweaks to my gps. route and the road conditions I forgot the most basic of rules, to keep hydrated.
250ml of water was never going to get me to the 300km finish.....Disappointed but ride and learn.
