OK Wizo here goes. 20 secs down the runway is quite a long way down by the way! Your plane is cleared to line up and take off with traffic say on 5 miles final (could legally be less). Your crew get the cockpit indication and decide to abort. They report this to ATC (tower) who will instruct them to vacate at the nearest exit, informing them of the position of the landing traffic. ATC then inform the landing traffic that they may expect a late landing clearance or possible go-around as there's one a/c still to vacate the runway. (The landing a/c will probably have heard your a/c reporting the abort). ATC and the pilot of the landing a/c are constantly monitoring the situation. If your a/c had not vacated in time the landing a/c would have not got a landing clearance and would have initiated a standard go-around procedure. All very normal and very safe. Your perceived scenario is only reserved for third rate Hollywood movies
