On the evening in question 26L was Notamed to close at 21.30, with a ten minute changeover period before 26R comes into use.
I arrived from Egypt with an eta 22.05 and was told by the French to reduce speed to Minimum clean when just north of Paris due to excessive delays inbound to LGW. On handover to London atc we were told to hold at Bexil, after going twice round at Bexil then told to hold at Timba for another 10 mins before being vectored for 26R. I don't know why the delays were so excessive that night as change over to standby runway usually don't cause that much of a problem. Hope that gives more insight into the evenings events.