Incorrect departuretime when using AirlineFlightSchedules


I use AirlineFlightSchedules and FlightInfo API on the same flight and the same date, but get the total different timestamp from departuretime and filed_departuretime field. The URL I used is AirlineFlightSchedules?startDate=1418574065&endDate=1419783665&airline=JL&flightno=097 and got departuretime = 1418661300. When using, I got filed_departuretime =1418686500.
It’s certain that the arrivalTime from AirlineFlightSchedules API and the estimatedarrivaltime from FlightInfo are also different and the difference is about 7 hours. Could you reply to me if I misuse the APIs ?