I have only one top bar hive. It overwintered as a small 8 bar colony and has started expanding and drawing new comb. I have been moving the backer one bar at a time and shifting the last comb to add a new bar in the empty space as they go. The hive is about 1/2 drawn out. Should I continue leap-frogging the bars or place the backer more toward the end giving them plenty of room to expand? If they continue to build is it a good indication that they are unlikely to swarm?
once you hit the main nectar flow, you may find you need to add more than one empty bar at a time. I like to leave at least 2 open on the end, but I do add empty bars into the middle of the brood nest on a weekly basis (like 3 checker boarded in) so that they never get so packed that they want to swarm on me. (they will get so filled up with nectar and all that I have to make a small split of 5 bars to give them more room to finish capping the nectar without swarming, but that is just my preference.)