5 minutes, simultaneous, an infinity in the past or the future. If our copy is infinitely far away, I think trying to come up with some sort of common reference frame is futile. Maybe it's more helpful to think of ourselves as 4d objects, if the 4d version of ourselves exists somewhere else, I'm not sure you could really ever say for sure whether they existed 'simultaneously' or not. As we already know that even within our own universe, time is relative.