In the end, have you actually changed the past?

The events of the past have not changed and neither has their sequence. The objects, the subjects—all remains as all was.

But their meaning is now vastly different. And that is all that really matters. Because nothing is real in this world, all is transient, here only for now, vanished in a time later, all except for meaning.

The meaning of each event, that is forever. And according to where you take those events, so will be their meaning.