Let's say I'm towing a black hole by using a spaceship, and a rope, and a mass that is attracting the black hole near its event horizon. Let's say the mass unfastens at some moment, and I'm watching everything carefully. Obviously I will notice that the mass has unfastened only after a long time after the unfastening happened. As I'm watching carefully, I should be able to see what exactly happened, including the reason why I saw the black hole being accelerated by my pulling action when the mass was already unfastened. So what might be the reason why I saw the black hole accelerating, when the mass was already unfastened?