Does your hive have an upper entrance? If not, drones might be trapped in there with no way out. Either you have put the queen excluder in and accidentally left the queen above it, or the queen got through the excluder because she is small or the excluder has a bent wire or something.....OR you had larvae/eggs already in the super and when you put the excluder in, the bees above the excluder raised a new queen from it. Or you already had a two queen colony before you put the excluder in.Found capped brood above queen excluder in honey super! Is that a problem?
Now that is very interesting, I had not heard of this before. :dontknow:Many times i have found drone brood above the queen excluder, (in fact just yesterday:roll usually on the bottom of a honey frame. My 87 yr. old ?beekeeper buddy says a strong hive with several supers will allow or tolerate some laying worker activity? The picture shown above is the work of a queen,could of been a new queen that layed above the EQ and made it through the excluder before her abdomen fully developed. Jack