For my ~dozen previous LHR arrivals, until most recently last week, by far the best seat for a view of London and River Thames during approach was a RIGHT (starboard) window seat.

Most approaches to LHR ended up East to West, usually over the Thames or a little south of the Thames at a relatively low altitude, allowing for a terrific view of many of the major sites in London. (Pictures below are of 3 different planes flying to LHR, taken several years ago from HMS Belfast* or near the edge of the Thames looking south. Clearly a RIGHT window seat in any of those planes would have a lovely view of the city and the river.)

Last week I sat in my usual RIGHT window seat but the plane flew a different arrival/approach and the LEFT side had the view of the city. Last week we flew west to east north of the city then made a right ~180 degree turn (to line up with the runway) but ended up a little north of the city thus the view of the city was from the LEFT window seats. I cannot remember if (prior to 2020) the usual flight path was similar with a wider right turn ending up south of the city or the usual flight path was west to east well south of the city with a left ~180 degree turn (to line up with the runway) ending a little south of the city.

Any other window-seat-ophiles fly arrivals to LHR often enough to explain? Thank you.

(* HMS Belfast is a Town-class light cruiser that was built for the Royal Navy. Arctic 1943, North Cape 1943, Normandy 1944, Korea 1950–52. She is now permanently moored as a museum ship on the River Thames (between London Bridge and Tower Bridge) in London and is operated by the Imperial War Museum.)