alright thanks a lot guys. this is sound advice.
just for info, the pre sale fares were around 650 gbp. I have been watching it for a while and it has been stuck at this level.
and oh btw, this refers to the nonstop flight only. I believe one stop fares can go down to under 550' but I really loathe the idea of having to go through security a few times on such a trip, not to forget the stresses of connections, and having to arrive at late night