It's tiered pricing by day of the week and/or time of the event. Some dates are still $80. In past years I know Wed had always been the cheapest day, but wouldn't work for me as it would mean I'd do the tour before going through the houses at night and that's no fun.
This year it looks like all of Sept is all $100 and October has dates that are $100, $90 and $80.
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