Re: drones at entrance
What you have is very likely normal. However, you won't know until you open them up and inspect. Make sure to check for capped brood, eggs, and larva. If you have this, you have a queen. Also, check for queen cells. If they have queen cells, they are either replacing their queen or are getting ready to swarm. Check for drone brood (it is much larger and the cap bulges out over the worker brood, it is usually in clusters). If you have ALL drone brood, you have a problem. If you have ~30% or less drone brood, sleep easy.
Try it. What could happen?