In a webmaster hangout, Google’s John Mueller made clear that Google will treat your new domain as a totally new website if you cannot redirect your old domain to your new domain:
“Ideally, [301 redirects to the new domain should be in place] even longer than a year. Sometimes you can’t control that at all, sometimes there’s legal situations where you say I can’t put anything on my old domain, I can’t put a redirect up there, and that’s life.
You can’t fix that, right. So from our point of view what would happen then is that we would probably drop the old domain and treat the new domain like a new site, like a separate site. That’s kind of the extreme situation, obviously you as someone who is running that business knows that area a bit and can probably get things sorted a lot faster than if you were really starting from scratch, but it is still a lot of work.”
You can view the video here:
