I saw this but the dates are 6 to 15 September and I was told that the last night was a Saturday night and the 15th isn't a Saturday so am not sure whether those dates are accurate.
I've seen it's the 6th Sept as well. If you are in or near Baza in August, don't forget Caniles feria, which is on 1st week in August, usually, if they have put the lights up around the town that is.