Danial,
I agree 5.8 needs altering and "FF's" wording is a good start. Perhaps another line along the lines of "where brevet cards are not used the organiser will agree in advance with the rider(s) which means of proof of passage, acceptable to AUK, will be accepted for that ride" Something like this, which I am sure could be better worded, would be flexible enough to be future proof, I think, and cover DIYs and Perms.
Bones