It would be when you buy the hive components but I don't think that is what you wanted to ask. A first year colony (queen) would be when the queen gets mated and starts her own colony regardless of the hive components. Typically a swarm. Even with the old queen because she will be replaced.And what is the definition of a first year hive?
If you know the queen is a first year queen why would you want to encourage the swarmy characteristic?I built 8 D. Coates nuc boxes over the winter and if I see any swarm cells this spring, I plan to put the frames with queen cells in separate nucs along with some brood and bees to make some splits.