yeah, there's a few of the penge lot, one who did it last year. weirdly the organiser hasn't sent an email with an updated gpx or anything which isn't great
you have "controls" at audaxes: info controls (where you have to answer a question); and full controls- these either have a person stamping your brevet (like the iow randonnee), or, if there's no one there, you will have to get proof of passage another way, like getting a receipt from a shop. the bit on controls here explains it: http://www.aukweb.net/events/riding/
it's a bit bonkers but quite fun, i found.