Maximizing airport runway & boarding gates utilization at London Heathrow

Have you transferred at or departed from the London Heathrow airport lately? Did you notice how the boarding gates remain unassigned until approximately 40 minutes before departure for the inter-European flights?  See picture below. I noticed them doing this at least 2 years ago, but now as an Operational Research professional, I can appreciate some of the intuition behind it.

It allows the runway and boarding gate planners a lot of flexibility so that if a flight is late, the planner can easily swap gates and runways if needed with minimum communication to the parties involved. In terms of communication, it is less hassle and less mistake-prone. In terms of an optimization problem, this flexibility means fewer constraints, and therefore better solutions potentially.

Interesting note: see how there are 4 flights scheduled at 19:05 for departure? My flight was the 19:05 to Prague, and I was able to see that there were basically 2 runways for the group of gates in my area, and several planes (about 4) were lined up like ducks in a row waiting for their turns to take off one by one. However, the individual take off is quite fast. Therefore, even though the 19:05 departure time is somewhat approximate for the 4 flights, my flight to Prague certainly arrived on time nonetheless.

As a passenger, it was slightly annoying that when I arrived at Heathrow, I did not know which gate to sit at to wait for my departing flight. However, I was quickly assured that this would not be a problem, because another information board tells me how long it would take to get from where I am to another gate, so I did not need to worry about being late for boarding. See picture below.

I suppose this could also be applied to the domestic flights in other parts of the world, such as the USA and Canada.