Prompts "from the future"

The paper states that "It is possible for prompted frames to also 'come from the future' relative to the current frame".
I found a "reverse" parameter in predictor.propagate_in_video() that seems to only revert the frame order. It that it or did I miss something more complex ?

I guess that the highest performance can be achieved when we add a prompt on an object while it is the biggest (more resolution) and less occluded/truncated. Then we propagate forward (reverse=False) + backward (reverse=True) to track it in the whole video.