Definition of occupancy not specifically give in the NEC but inference from description in related portions of code can be made. Article 230 starts off restricting 1 service to a building in 230.2; in code reference to service conductors 230.70 a means to disconnect all conductors in a building from the service conductors, in 230.71(A) it further refers back to 230.40 including (exception 1) tieing a disconnecting means to service conductors and occupancies. Thus inference 1 disconnect 1 occupancy.
What your drawing appears to show maybe permitted not in reference to 230.40 but to 230.2(A),(B),(C),(D) but more specifically your statement indicating it might be covered in section 230.2(D) might be applicable.