For the little it is worth, the following may shed some light on cabin crew work practices.
In March 19th one left London for Doha on Qatar. The flight departed LHR at something like 20.00hrs, one forgets exactly. The crew in the class in which one was flying were going to go back from Doha to Paris that evening, the 20th, and were going to night stop there before returning to base sometime the following day, the 21st. Now, that is only two sectors, London - Doha, Doha-Paris, but it struck one that it was a very long old duty and the crew, who incidentally were Malaysian, whilst being philosophical about it all, were not really very happy.
Again, for the little it is worth, it stikes one as though Qatar tends to use more of its Arab cabin crew on the routes southwards to Africa from Doha than they do on the European routes. It also strikes one, from observation as well as personal experience, that the Qatar Arab crew are absolutely terrified of putting a foot wrong, to the point where their behaviour towards passengers can become quite aggressive, and that this does tend to restrict sponanteous decision making and pragmatic problem solving. One can of course, entirely understand this whilst in no way subscribing towards it.
Oh yes, sorry, one notices that you are newish to Pprune. One is a sometime airline pilot who does a lot of travelling for fun. This means that perhaps one knows what one is talking about, or then again....?