Atlanta is typically 13 hours behind Hong Kong. When it's 9:00 PM in Hong Kong, it's 8:00 AM the same day in Atlanta. Hong Kong does not observe daylight saving time, but Atlanta does.
During US daylight saving time (March to November), the difference is 12 hours. During US standard time (November to March), the difference increases to 13 hours.
Optimal meeting window: 7:00 AM - 9:00 AM Atlanta time (7:00 PM - 9:00 PM Hong Kong, or 8:00 PM - 10:00 PM in winter). Early morning Atlanta catches evening Hong Kong.
Several major US corporations headquartered in Atlanta, including Coca-Cola and Home Depot, maintain significant Asia-Pacific operations through Hong Kong.