All of that is checked upon inspection as well. If I see that the bus is within a couple thousand miles of an oil change, i'll do it then and there to get it over with.
As far as next service date, that is also included in inspections. It isnt tagged on the bus, but in my records (which I have saved on my pc) there is service info. The problem with an RP is that we cant really calculate how many miles a bus is going.. so an oil change every so many miles is tough.