Threatening skies over Wellbottom Down (click for larger image)
On the way back, as posted on the Oxon Birding Blog, back in Oxon, there was a pale Buzzard sp over Sparsholt Down at about 17:00, viewed from the minor road that runs south from Kingston Lisle towards Lambourn. It was initially over the wood at about SU330843, before drifting off to the north.
It appeared very pale underneath and most interestingly the upper tail showed a large white rump with dark terminal band. Unfortunately, it was too far away for my available reserve bins to see any dark belly patch and I didn't have my camera with me. I can't claim Rough-legged given these views but it was a possibility I couldn't rule out.