We left the gate early. Right before takeoff the pilot announced that there's a mechanical issue that needed a quick fix, and returned to the gate.
At 2:00am they announced that they reached the curfew at 1:40 but got it extended to 2:00, but that was still not enough time and the flight was cancelled.
Everyone needed to do immigration again and luggage has still not come out. Hotels in the area are fully booked but they said that they are working on something.
Meanwhile flight has been rescheduled to 6:00pm and everyone is being automatically rebooked.