I didn't think we were and I'm now confused about what we're talking about, and since our discussions start with us talking about different things and ending in an argument because we're having two separate conversations, let's slow down. What exactly are you saying?
The reason we're doing this careful is because a) the bus probably thinks we're only freeing the person that shouldn't be here and b) we didn't know who wasn't supposed to be here. We had no idea of the situation. But mostly, because the bus said that it's a situation in flux and we might need these people to trust us.
The term 'ripple effect' as applied to time travel is a term created by a movie and not used in scientific books. Ergo my question if you had watched the movie.