I'm planning a trip to Trento and planning on making several trips there by bus - I've found some timetables on their website (example: https://www.trentinotrasporti.it/pdforari/extraurbani/linee/OrariDiDirettrice-E21I-202INA.PDF) on which some services are marked as "Bus Privato".
This literally seems to translate is "Private Bus". Which presumably means they are not open to the public? If that is the case what purpose do they serve and who are these buses for? They do not seem to correspond to school times and seem to run the same route as other public services, they also don't seem to show on online journey planners. Why include them in the public timetables at all?
Is it possible for members of the public (or large groups?) to pre-arrange to use these services?