We left last year on the 30th Oct and they had started putting up Christmas decorations so Im assuming most Halloween things will start coming down on 1st Nov.
This is the first year were going in October, historically we have always gone the first week of November and we love it because we still get a little bit of the halloween decorations and a little bit of the Christmas decorations. I remember one year, when the CALIFORNIA letters were still up, that we saw then decorated for both holidays in one week, very cool and by the time we left at the end of the week the castle already had snow on it, it was very cool!