Tulsa keeps Central Time, UTC−6, an hour forward from March to November. During daylight saving, 08:00 in Tulsa is 18:30 IST and 20:00 is 06:30 IST, so a coach group's whole day on the road happens during the Indian night. In winter, add an hour.
That shapes the desk. Itinerary templates can be scheduled from India in the afternoon to land before breakfast in Tulsa. Questions from the road arrive overnight, and a night shift in Mumbai or Pune answers them in free form inside the 24-hour window. A lost passport is a different matter: Oklahoma falls under the Consulate General of India in Houston, and the template that explains what to do should say so.