Several older references say that if the frame is at least 2/3 capped, it's all right to extract. Last September, I put frames in my hand extractor without cutting off the cappings first. I gently extracted all the uncapped honey first (a little watery), put it aside for myself (just in case it fermented, don't want to sell or gift any of it), then removed the cappings on the rest of the frame and extracted as usual. I'm still using this "uncapped" honey and it has been absolutely fine. My guess is that it was close to being capped that late in the year, so the moisture levels were fine.