It would be helpful if DTG added a return to timetable option after completing a service, along side the return to main menu option. This would save a lot of menu hopping. I don't know if there are other ways around this?
But that option is not very consistent, sometimes it's available and sometimes not. Not figured out yet why.
Return to free roam does not take you to the timetable or any other menu, it simply allows you to continue and get out of the seat and do whatever after that, so nothing like a return to timetable option would.