I've been watching a few videos on Youtube where the runner hits the box to start the bridge and waits for the first couple of boxes to spawn before running across a few and jumping to the end to break the last time box. Can anyone explain this to me? Ive tried it a few dozen times already and have never succeeded in pulling it off. Im playing on PS4 if that makes a difference.

Any help on improving on this level is also appreciated as well!