To Fondant or Not To Fondant ?

In the winter beekeepers are advised to heft their hives to gauge the level of stores. If the hive is light then the advice is to feed the bees with fondant- a boiled icing that the bees can access readily instead of having to process like the syrup that is fed in autumn or spring. Here I have followed a recipe that boils together sugar,water and glucose syrup, once 240F is reached the fondant is kneaded until malleable. This can then be packed in to trays and put directly over the hole in the crown board .
The question now is when is the optimum time to put the fondant on - but I at least have a couple of blocks ready if the time seems to have come!