Only about two hours, and yes, east - West is a lot worse. That said, trying to sleep before a long night was not always easy, particularly in summer.
...but fatigue, not just tiredness, is not just about one trip, its the accumulation of repeated difficult flights.
Looking back at my career I remember that as the worst night’s work but perhaps time dims the memory !
I see fatigue is being discussed again in the BA pilots strike thread.