If you are taking joint flight, they will put you to another flight, but if not, they might neither change your flight nor refund you. To make it easy, you can take the 12:00 flight. After arriving at the airport, you can take Airport Express Bus 2 to the terminal and then take taxi to Dongpu Bus Station(东圃客运站), there are buses to Meizhou at 19:30 and 20:10.