I was posted to LHR in '89 and 05 was still in use around then as I can remember watching it in action and working it as a tower u/t. It only went out of service when they decided to build some parking stands on what was the 05 threshold.
Sat on my desk beside me is a (the?) 05 runway designator strip, that I liberated when the runway was finally withdrawn.
Once they'd built the stands on the 05 threshold, that was the main reason it then took so long to get 23 up and running. Any aircraft and associated equipment parked on the 05 threshold stands had to be removed before 23 could be used. I recall it either being 2 or 4 hours notice required.