Strange Bee Behavior

I am hoping my bee mentor can tell me what this means. Today the bees in the new hive are busy coming and going. Except for 5 or 6 bees, lined up like sentries, in front of the entrance. They are standing stock still, like the Queen's Guard. The only movement from them is the fanning of their wings. The other bees are climbing over and between them, but they remain unmoved. Wish I knew what they were doing.

At least they have stopped chucking out brood right and left.