I suppose it's merely semantics, though I have seen individuals from the same reality, taken from different points in time.

[But that is also a rather large of can of worms that is likely best left alone for the time being. These tunnels aren't exactly safe, after all.]

If you want more answers, we should vacate these tunnels first. There's a clinic and a library that offer resources without the risk of angering the resident Dugtrio.