I made some interesting observations in my tbhs today. I shook bees into them about a week ago. Initially, the bees ran to one end of the top bar hive and loosely cluster their for 3 to 4 days. One tbh went towards the end with the entrance and the other toward the rear of the hive. Lots of little gobs of beeswax were deposited that area and one hive constructed a small hand sized piece of comb there.
But after they got their bearings, shaking bees from a functional hive into an empty box must be very traumatic for them, both clusters recentered themselves on topbars 3,4,5. First comb was constructed on topbar 3 and more extensive comb was constructed on topbars 4 and 5 with about 9 inches of comb on half their lengths.
Initial construction began on the half of those topbars away from the hive entrance. This is the same location and pattern of construction noted in my tbh last year. Although last years entrance was on one side of the end. And this years entrance is on one end of the side.
Preliminary examination of the cell size on these combs show that the same pattern for tapered cell size, as was seen in last years tbh, is being repeated. The combs start at the topbar with a couple rows of drone sized cells. Cell sizes gradually taper to small cell size at the bottom of these combs which are about half their finished heigth.
The tbhs are New World Carniolan and Russian.
The patterns I observed last year are being duplicated. The bees have scoped out their cavity and are building a broodnest with a structure and purpose.
Every comb in mine is full of brood except for the edges. So I'd have to say they have a plan for the brood nest. I suppose when they get to where the edge of it is they will fill a comb with honey.