I will be going on a flight that is supposed to arrive at Heathrow at 5 am. I have a car collecting me at 6 am, which should be about right, assuming the plane is on time, and immigration and baggage takes the usual amount of time.
However, I've taken this flight before, and had the plane arrive significantly early, and immigration take no time at all. On that occasion, I was departing by train so I immediately left.
But if it happens this time, I will be left with some time to kill. Is there and food or coffee places near arrivals at Heathrow Terminal 3, that will be open at 5-ish in the morning?