^^^ Last year I flew SIN - Cochin with Silk Air, about a 4.5hr flight, left Changi about 8pm, with the time diff due in about 10.15. I asked one of the crew how long they stayed over and she said oh no, we go straight back after a one hour turn around. With my rudimentary maths, this makes at least 10 hours, without whatever has to be done before the flight.
I'm not sure this can be right, but seemingly it is. Our particular flight was delayed by more than an hour as well as I recall; it was nearly midnight local time when we landed, so that crew must have done 12+ that 'shift'.