Afraid not, I can only hazard that whatever criteria they use isn't specific. They look for people who meet their standards and take them wherever they find them.

Though if it's a comfort when they send you back it should be to the exact moment that you left.

[At least in her previous experience. From what she's heard around the place it's the exact same scenario in Exilium too.]

There's a single totalitarian government in place which controls the entire world here and the Intiative is rebelling against them. From what I understand the Initiative's people didn't have a chance against the United Earth military alone and the only way they had to recruit help was the technology to pull people from other worlds. So that's what they do and they send us on missions to try and change events in the past so that the United Earth will never exist, or will weaken enough to be defeated.