Granted this is WAY too early, but have to ask due to some frozen frames,etc. When can you harvest in regards to capped vs. non-capped cells? I never really see 100% capped, so what is ok to extract?
The thing you are trying to avoid is nectar that is too runny and will ferment. When it's 2/3 to 3/4 capped it's pretty much honey. If only a little of it is capped it's not done yet.
The other thing is how runny is it? you can take a toothpick or something and put it in the cell and pull it out and see if it's like water it's not done. If you uncap a cell and try it you'll get a feel for how thick it should be at that same temperature.
Also, if we are talking about things that were in the hive all winter, they are not uncapped because they are green (too wet) but because they were feeding on them. They are probably LOW on water conent from evaporation from the open cell, not open because they were HIGH on water content.
Open and capped are just a way, in the fall, to tell if the nectar has been made into honey yet, because the bees won't cap it until it has evaporated enough. When they uncap it to eat it it's still honey, and in fact it has exposed surface and will not continue to evaporate until it crystalizes. In the spring, it's had all winter to evaporate.