well that is strange then... are you talking of them heading east before epsom?
this has never happened while im in, and have not heard of any colleagues mentioning it......but not to say it doesnt happen.
are you sure they arent out of 4000? as we do turn them early (before EPM) if heathrow inbound traffic permits and climb them, but still, only after 4000ft.
if they are would love to know why though.