Since my last update from Site 3. was in Early October.
Through-out the fall till now, the female (most likely) had been switching up from the pole box to the SQR type box. Earlier in the fall spending most of the in the pole box. Then what seemed to be an even split. Now, it seems may be more in the SQR type box. The male seems to still be elusive. At least both boxes have not been occupied at the same time.
(the pole box photo was from Sept.)