The house bees clean the cell and probably add a pheromone to identify the cell as being cleaned. The queen lays the egg, about 73 hours later it hatches and the nurse bees immediately add the first brood food.
That is an interesting statement that im looking into. I wondered if the bees brought the feed into the hive and placed it onto the stores frames first or placed it onto the brood frames for dissemination.You might’ve seen some nectar that had not been consumed or moved into storage also.