Drone Laying Workers.

An old or badly mated queen is prone to becoming a drone layer; it's a result of the way the sexes are determined in the order, Hymenoptera, that is the group of insects covered by the ants, wasps and bees. The males are produced from unfertilised eggs, so they only have one set of chromosomes which they get from their mother, while the females are produced from fertilised eggs and so have pairs of chromosomes. The queen only goes out on one mating flight (allegedly) and will mate with twenty or so drones so comparisons with your own family members may, or may not be appropriate. A young queen may not have mated, or an elderly one may have run out of sperm, resulting in a drone laying queen, she thinks she's producing females (workers) but can only manage males. Since a drone is normally bigger than a worker, it's larva needs a larger cell than a worker would and so they tend to bulge a bit at the top.
However, the queen that should be heading this colony is still young enough to go out on mating flights so I think I need another explanation.

When a colony is hopelessly queenless, the lack of queen pheromone stops inhibiting the workers from laying eggs; again, they can only lay drone brood, this time, because they are unable to mate; however, not being designed for the purpose they can make a mess of things: their laying pattern is haphazard as this is, they can't reach the bottom of the cells so the eggs tend to be on the sides of the cells and they often lay more than one egg in each cell. Close scrutiny of the cells at the centre bottom of the blip shows single eggs at the bottom of the cells albeit, not quite as central as I would expect.

At the end of the day, the precise nature of the problem is unimportant; the books say that neither is worth the effort of saving as there is no reliable cure for either. However, I know that this is a new condition for this colony so the habit should not have become too firmly entrenched – yet; and I also have a strong queen-right colony next to it on the same stand.

One executive decision, a calculated risk and ten minutes later, The two colonies were united and, a fortnight further on, I can report that the operation was successful and the colony is now strong, queen-right, and still has time to supplement this year's honey crop, not by much - but every little helps.