We have rules stating the maximum time frame we must go between calling/contacting the pilots at my airline. Most if not all have similar rules, if you are concerned with the pilots falling asleep do not worry on the 767(a lot more outdated than the birds you will be flying on your trip) there are alarms to wake them up if they do not press something within a certain time frame.
I have used Qatar Airways and they are superb. They are professional beyond doubt.
I have used this example time and time again, when I was travelling LHR-DOH a few years back with them I just licked my lips I was then a passing CC noticed this and went and got a glass of water for me and asked if I was thirsty then offered the whole 1.5ltr bottle of water to keep, Maybe in First or Business class this maybe standard, I don't know but in economy it was definately going above and beyond and not expected
