I believe the Volt gives far more statistics like miles on electricity and miles on gas. It would be nice to know.
As far as oil changes go, most automobile manuals will say a certain mileage like 5,000 or 7,500 miles then they will say something along the lines of “or 6 months, whichever is sooner”. That is because once oil is put into service it starts to collect contaminates and is less effective. If it’s been >6 months you should change your oil anyway regardless of miles/hours on the engine.
While we are on the road topic, it is a best practice to start engines and “excercise” them from time to time to keep things lubricated and running properly.