The time shown on the itinerary/receipt is the departure time of the aircraft. Flight departure time is not the same as the time you must check-in or the time you must be at the boarding gate. The airline may refuse to carry you if you are late. Standard opening of check-in desks vary depending on where you are travelling from and to. Please see the below table for more information:
All times are prior to the scheduled time of departure.
Long haul (7+ hours)
All check-in desks close strictly 1 hour before the scheduled departure. Failure to check-in in good time will result in you being denied boarding to the flight.