I have an odd trip, because my travel plans changed I am flying to Paris via LHR from YVR, but now I want to stay in London. I called BA to change my ticket but it has been tough getting through to them. My travel agent says its $450 to make the change I need through them so I figured it would be easier just to fly to Paris, and then fly back to London as it only costs $80.

So my question is how long I require for the connection to fly back to London. I assume that if I take the same flight back which is 30 mins later I should be OK?

Thanks in advance.