Whether or not there is daylight outside, the blinds will be shut and the lights will go off. One of my bugbears is that most LH services these days tend to turn into dormitory services after the first meal service. Although in principle you can keep a blind open, I can never escape the feeling the rest of the cabin hates me for letting in brilliant shafts of light.

I've done a lot of returning from SE Asia in all cabins, and the one I like least is Premium Economy, because although you get a bit of recline, the hard armrests make it a bit uncomfortable to sleep in, I don't feel I'm getting much more than I do in Y for an often very large bump in price. If MH is an option it's OK in Y; BA is patchy in my experience, the crews seem less attentive. It would take a lot of persuasion these days for me to contemplate this length of flight in anything other than J or F, it's a long old flight and being able to sleep well for 7 or 8 hours at some point in the flight is very welcome.