What time do the baht buses and regular small buses start and stop for the day?

I stress that I am not a resident. In the early 2000's, I used to spend time there. Combining my memory with my general knowledge of elsewhere in Thailand, you should be able to count on service from 6:00 a.m. to 6:00 p.m. I seem to remember that in HH, the last songthaew was at 7:00. Ask the drivers, or fellow passengers.