Me too - Apparently I've 'not yet started', but there's some graphic photographic evidence to the contrary. I scrambled late through the start because I was in the jam, so have been blaming myself (perhaps I scurried through a dead zone?), but 500 people? Perhaps it's something to do with those flimsy 'chips' ...
Loved the race by the way, and will be back next year. I never knew that Oxford had hills.