hmmmm . . . I have just watched the video again many times in slow-mo, frame by frame at large res, and yes, it is weird.
The Bird/flying thing or whatever, does get almost to the edge of the building then all of a sudden is back about half a second in its travels, like the video has jumped back a few frames, then continues on again!!!
all while the video itself is only playing forward which is evidenced by everything else in the video only moving in normal time with no reversals or jumps in frames.
