[JWPalmer]

High levels of humidity and poor ventilation within the hive can prevent or at least drastically slow dow the curing process.

FWIW, my bees will cap the honey at 19.8%, much to my dismay.

 

[JWPalmer]

Alea iacta est. You will be fine if you keep the sugar bricks on them. I just added feeders to my last 4 hives. All had a fair amount of capped syrup, but not the full medium supers I like to over winter with. Temps here are still above 90° F. during the day.