First a terminological quibble. By "scientifically impossible," I take it you mean "technological infeasible," i.e., impossible given the limits of current technology. As I see it, what's scientifically possible or impossible depends only on the laws of nature, which are standardly taken to be unchanging over time (or at least over any time that humans will experience). I think the jury's still out on whether backward time-travel is scientifically impossible in this latter sense.
To your question: I think there's something self-contradictory in the idea of "correcting what you did" if that means "bringing it about that you never did what you in fact did." Either (1) you did it, or (~ 1) you never did it. I can't see how any consistent story features both (1) and (~ 1).
In that sense, then, there's no such thing as (2) "going back in time and changing things in reality" and therefore nothing that's the "same as" (2). See section 1.2 of the SEP article on time-travel.