How are on-the-spot speeding fines generally structured in the Cayman Islands, and what happens if the fine is high enough?

1. A single flat fine applies no matter how far over the limit a driver was travelling
2. Fines only apply to commercial vehicles, not private cars
3. There is no financial penalty, only a verbal warning for a first offence
4. A fine is charged for each mile per hour over the limit, and if the total exceeds a set amount the driver must appear in court, risking licence suspension