Ah yes, Flightwatch, you must have been flying for BEA at the time that they were trying to make all their aircraft "Super", when they were not that super really.
There was certainly a reduced "coffin corner" problem with the improved wing leading edge fitted to later 500s and, I believe, 475s.
Doubtless you will correct me if I'm wrong, but I recall BEA aircraft had the front airstairs replaced with a weight to appease the step-pushers union of BEA. As built, they were also short of water injection and the drooped leading edge. Not so Super really although the flight-deck cupholders were moved slightly from standard in the BA build specification! What profligate money wasters there must have been in certain areas but they managed to get away with no drop-downs!
I understand that, at a similar time, Boeing refused to allow BEA to brand their original 737s the "Super 737" as it would have implied something that it wasn't and thus pee of other customers!