Four Service Disconnects for one residence? Am I missing something?
Doug if I remember you are a Chicago resident?
If so you may have some different rules for this.
But the NEC allows up to 6 (7 if there is a fire pump) disconnects for the "service disconnect" to a structure.
There are a lot of ways this could happen, one way would be a 320/400 meter socket feeding four 100 amp main breaker panels side by side.
Each one of the 4 breakers is a service disconnect.
In commercial applications service conductors may enter a piece of service rated switch gear with no single main.
In that switch gear you might install six 800 amp breakers giving you 4800 amps of service with out the need of a very expensive 480 volt 4800 amp GFP main breaker unit.