For the 48hr (2 pilots) DKR return sector you have 10 minutes to spare before going in discretion. Personally, I think the return through the night is worse than the flight there, even though it's shorter.
When I read safety summaries, I am always amazed by the lack of fatigue ASR's. EK304/305 should be in there 7 days a week. You might find it 4 times a month. The 777 flight gets an augmented crew, not for legality but to mitigate fatigue (email from crew controle). The AB flight is not augmented because our arrival is at lunch time (circadian high) and there are NOT ENOUGH ASR's (email safety dep).
If you don't write, nothing will change and that is a certainty.
Happy flying
T