Adding more space to the hive, is it another brood or super, depends on the amount of bees.
When bees burst out from entrance, the it is better add boath, brood and super at same time.
Number of brood tells that after a week you must add a box again, or two boxes.
I have never looked the number of brood frames when I add super.
If you do not know, when to add the box, put it under the brood, and it cannot go wrong. Heat of the brood will be stored in upstairs. It is a way to see, how much the queen can lay.
My queens are allowed to lay everywhere. Main thing is, that it lays a lot. If she lays only one box, she must go.
It is really strange how difficult it is to the English beekeepers to use douple broodboxes. If two is too much, then move the place of excluder.