Achievements (Metal Gear Solid 5: The Phantom Pain)

There is an elite achievement, that is, to complete all missions with rank s, so right now I am performing missions with this particular rank, but here is the prologue where there with an ocelot fired back from the fiery Volgin (half of it may not even be in the subject of who it is, okay), there should have been do not miss a single shot, and so there I coped with the rating b, in short, the prologue can be replayed without starting a new game?