I'm running all deeps, and have been experimenting with unlimited brood this year. Took the excluders off because we averaged more swarms than the number of hives.
In several hives maybe I expanded them too quickly. After I moved some brood up, the queens stopped laying in the bottom. The bottom boxes are being used for pollen, but otherwise are all empty cells. No new eggs. Some of them are putting nectar down there below
the brood nest.
I'm in an area where SHB is very bad, so it's concerning having this extra space. There is a nectar flow. Would it be good practice to let the bees backfill the top with nectar, and will the queen move down and lay in the bottom again?