I remember @Doug1 was intrigued by idea of “fall comb buildout” 
This year I added a second brood box (10 frames with wax foundation) to a new colony at the end of April. At the beginning of May, they built three middle frames. This is how the first and second outer frames look now.
By the way, it is the strongest hive now.
I guess it would be the end of the colony if tried in the Alberta region