It turns out that Zager and Evans were more optimistic than Joss Whedon: he thought that Earth That Was would be used up more than 7000 years earlier. Still, it’s the same destination: Earth completely used up and nothing left, an ecological crash from which there is no recovery.
Indeed, there may not even be any humans left to see it – presumably 9595 is the point where the last microbes can no longer make it, either.