Strong overwintered colonies should have two honey supers on right now. The supers should be checked every five days during this nectar flow. If the hive fills one super and has nectar in the second super, two more supers should be added. Stay ahead of the bees or they will pack the brood nest with honey.
Unfortunately, package bees and nucs are still too low in population to get a crop of honey from Black Locust. But the package bee populations are getting larger. Everyone that has put in package bees should have their second boxes on by now. Package bees still need to be fed if they are still making comb. With the increasing population of bees, the making of comb will be speeding along at a faster rate.
Colonies are changing everyday. Populations are on the rise. The main nectar is on the horizon.