Sam nods, slowly; she wasn't around for that particular mission, as SG-1 was offworld at the time dealing with the Ori, but she knows about it. "Okay, that helps. Well, like I said, this place is some kind of spatio-temporal anomaly in which people are pulled at random from other universes and timelines. It's a little like the ways we've had other versions of us from alternate timelines cross over into our timeline with the quantum mirror and other things except that we can't figure out what causes it. I am actually from a point about two and a half years further along in the timeline than you are, and I've been here almost three years."

She waits a beat to let that sink in, and then adds, "There was another you here when I got here, from a lot further back in the timeline."