I am US citizen traveling to Hong Kong via Beijing. below are my flights details


Landing in Beijing Friday, 2 October 2015, 08:50:31
Departure to HK Monday, 5 October 2015, 12:00:00
Result: 3 days, 3 hours, 9 minutes and 29 seconds

If I count total number of hours based on the flight times I am over 3 hours 10 minutes .I would like to know if I will ran into any issues any the airport? based on the Wiki I should be fine as the 72 hours count begins at the following day. Can anyone please share their experience?