Hmmm, if they are witches then it is more than possible that the Saturnalia could go on longer than that. I know that ordinary humans certainly can and do. I'm thinking 10-14 days would be a good stretch spread across four or five cities with a number of creative scenarios thrown in for good measure. And from what I've seen the average woman is pretty capable of that sort of witchcraft but maybe she requires those mid-week days to build up to the weekend and recharge from your four-day binge?