I would put some sugar (either candy board or mix water and sugar so it holds togaher and put close to cluster. Your problemwas caused by no fall flow...always watch your bees...IF they have no nectar coming in in Aug/sept you need to feed some 1/1 syrup those months to stimulate the queen regardless of how much honey is in the hive. THis is expecially true if you have Russians or carnolians. Some beeks like the idea that russians quit laying and it conserves stores...doesnt do much good when they die or so weak coming thru winter how much stres tehy have. It is hard to stimulate Russians...thats why among other reasons commercial beeks and anyone with years experience stays away from them.