That means that in 6,600 miles you will have to perform Service B which includes all of Service A. Plus the replacement of the cabin air filtering system, wiper blade check, brakes and ball joint check, brake pad check, alignment check, lubing of all lube parts and hinges, etc. You can see this all in the service manual what they cover under Service B.

And yes if a car has been sitting at a lot for 1 year without use the oil, it should be changed because first off the computer will probably tell you anyways that it needs it.

Also you might ask as to why you would need Service B if the car is new with very low miles, well again FSS is a life monitor that determines what services are needed. And since Service B includes lubing of parts and check and replacement of fluids it not only calculates it by miles but also by time that the car has been sitting so if the car is new with 100 miles on the odometer but it has been sitting at the dealer for 1 year and a half it'll probably want service B due to the time those fluids have been sitting in the car without use.