I've seen it a handful of times in 35+ years. It's likely I missed a couple other handfuls. One of my most prolific queens ever worked along side her daughter for 2-3 months, only disappearing in the fall. It's one of those unexpected wonders that makes beekeeping so enjoyable. I couldn't help but check in on the duo far more often than I should/would have, but they didn't seem to mind.
