There's no going back, goyim. Time is an illusion created by matter an space. Time is only defined by relative motion of matter. It's not some dimension you can travel.
The only approximation to your desires, in existence, is the backup system. This is just brute forcing everyone back into the positions they were at at some time and wiping their minds. Though some memories persist through the wiping in the soul or whatever.
I don't think they'll let you use it unless you destroy the world in such a way that they must go back so far to prevent it, supposing they don't immediately kill you and wipe your mind at the first sign you'd succeed. And most likely tortured into submission, too.