If this is a photoperiod plant, going to 11/13 can stop the reflowerings from continuing and encourage the plant to finish.
I imagine, if this is an auto, reducing the light cycle by 2 or 3 hours would have the same effect.
I would try the light reduction for a week then chop, if there are 90-95% brown pistils, otherwise continue with the reduced light cycle until there are 90-95% brown pistils and harvest then.
Hope this helps, Organoman.