Before you can start to claim anything you need to ensure that 24 hr messing is not available. I don't know your situation but if you have a need for 24 hr messing then the system should provide. If it is more one of convenience rather than lack of provison then no chance.
Once, when I was on a rota 14 hr night/10 hr day, I used to get a packed lunch, after breakfast, before going to bed. Naturally I would wake around midday but with the packed lunch in the room did not worry that I could not get back to sleep, would miss lunch, and spend the afternoon hungry. Without that pcked lunch I would have been tempted to get up. With the comfort blanket of a packed lunch I would drop off to sleep again and then put the packed lunch in the bin.