LHR alternation in strong winds
Can any LHR people explain the logic behind allocating the landing runway over the last few days? I was flying Friday prior to 1500 with 27R as landing runway and anticipated returning to LHR that evening to land on 27L. When we got back we were surprised to find that we were still landing on 27R despite warnings on the ATIS of turbulence and windshear in the last few miles, mainly caused by the winds blowing at about 240/40-50 over the hangars. After a couple of go-arounds and a report of mod to sev turbulence on short finals the landing runway was swiftly swapped to 27L. This leaves me with two questions:
1. Why were the runways not swapped at 1500Z as normal.
2. Why do the powers that be persist in trying to land aircraft on 27R when the winds are patently unsuitable?