I'll be there, just trying to work out which bike to use.
To be honest the only iffy bit regards to the wind is likely to be the Severn Bridge as long as you use the Northen cycle path (going by the wind direction from the weather forecast) it shouldnt be too scarey. The first bit is through lanes with high hedges providing shelter a reckon a bit of a head wind from Wormelow to Chepstow, cross wind across the Bridge and then a helping hand after Malmesbury. Mind the 2 or 3 inches of rain might be unpleasant.