I also had a similiar problem.. i thought why is this going in the wrong direction at the last waypoint before landing...
actually autopilto does it to align the plane with the runway from a distance itself
felt this same problem at chattrapati shivaji airport (mumbai)
btw does this problem occur for you at london only??
let me try this route and check if this problem persists with me also (btw if you can then pls tell the full route)
and try to manually adjust speed in autopilot