Flights from Chicago to London
Book this route, and I keep checking the price. If it falls before you fly, I buy the cheaper seat and send you the difference.
Why this route is worth watching
Chicago to London is booked well ahead, and the fare keeps moving after you buy. That gap is the whole point: when a fare falls after purchase the money is normally the airline's to keep. I check your price every few hours for as long as you hold the ticket, and if a cheaper seat appears I buy it before cancelling the old one, so you are never left without a seat.
Some fares cannot be changed at all. I tell you which before you buy, rather than after.