Finally did it!
Xmas Eve, up early and 110km done before lunch so minimal family grief
Xmas Day, sit back and relax.
Boxing Day, 145km, dry, sunny but bloody cold. Main issue was finding a shop open for snacks.
The next day was the biggy, a DIY Perm of 245km to my inlaws to make up the remaining km. Started badly as there'd been loads of rain, and about an hour into the ride it started again. My hands had gone numb by 40km in the freezing rain, after a warming coffee in Wymondham I encountered a flooded road blocked by a fallen tree in Cressington. Not long after I punctured but luckily my foam aerosol saved me from putting a tube in.
The Dutch Hills between Downham Market and Wisbech were tolerable as at least the rain had stopped. As I passed through Rutland it was clear this was were all the snow was and some of the ungritted back roads were sketchy. Slow on the way up as I couldn't stand without slipping and then on the way down so as not to crash!
Made it 228km to Sileby but the road to Mount Sorrel was flooded. So near to the finish I thought sod it and rode through. Nearly made it to the other side but my rear wheel picked up some submerged debris that wrapped the rear mech around the cassette the wrong way. The mech hanger was bent, the cage detached and by the front mech and the chain was behind the cassette. As the wheel was locked I had to carry the bike as I waded through knee deep water.
Sadly a DNF for the Audax but it was enough to take me over the 500km. Maybe next year my wife will relent and just allow 8 short rides....