I have a langstroth 10 frame standard hive. My bees seem to have been congregating on their entrance more so in the last few days. Recently, when the bottom two boxes were filled, I put on an excluder and another box. These two events correlate. I keep thinking the bottom two are so full that bees can't get to level 3 but there are more and more in there daily. Scared of swarming. Can no longer do inspection (removal of frames) on bottom two boxes.