Hello ss2010,
Those questions could be easily answered by your dealer...
The onboard computer informs you in real-time about the service deadline, by counting down the remaining mileage before service. I do suppose (my X1 isn't near that service time yet) that as in other Beemers a specific icon will start to flash when you get very close to service time.
As for a service manual... Gee, there are a few books delivered with the car, if it ain't in it go ask one to your dealer and then
!
I'm not sure about your comment on tire pressure.... In Oz and elsewhere there is a reference grid on the door jamb and that's that. Check your tires and if they are overinflated adjust accordingly.