Today I've seen several drones around Colony 1. This shouldn't be a surprise. April is swarming season so colonies which are preparing to swarm will be rearing Queens.
The drones have fully formed wings but appear to be unable to fly. I've found a few just walking around. I threw them into the air but they didn't fly. They might be suffering from a paralysing virus.
Early drones may be more likely to be affected by Varroa infestation because there are fewer of drone larvae early in the season, and the Varroa viral load can be more concentrated.