OK, to replicate that record in a 155kt TAS plane, one would need to keep fuel stops to under 1 hour approximately.
At that rate, London to Cape Town would be an astonishing feat of endurance - the GC distance (EGKK-FACT) is 5202nm and one reasonable airways route (FL130, low airways) is 5466nm.
It would be about 35hrs' airborne time; not sure if a pilot can stay awake for that long but I suppose one could sleep while on the autopilot... so long as it isn't a Honeywell KFC225
