Do I need to add a BB?

[GillGM]

I have 11 frames in a national BB that had an artificial swarm in four weeks ago.
~ 8 frames are full of brood,
~2 food frames
~1 frame being drawn out
~three supers, two full.

Although no signs of queen cell building on last inspection should I add a second BB at this point in season as overcrowding may restart swarming or will queen adapt her laying rate?

 

[Erichalfbee]

I might consider making sure the "empty" super is over the brood box and moving the QE on top of it giving you brood and a half.
The queen should be slowing now.

 

[Finman]

I have 11 frames in a national BB that had an artificial swarm in four weeks ago.
~ 8 frames are full of brood,
~2 food frames
~1 frame being drawn out
~three supers, two full.

Although no signs of queen cell building on last inspection should I add a second BB at this point in season as overcrowding may restart swarming or will queen adapt her laying rate?

8 brood frames produce quite much new bees. You need boath super and brood space.

Do it before you see the signs.