Performing any type of domain rebranding, the process of pointing a domain, subdomain, or other online content to a new domain, requires some maintenance for SEO purposes.
If you want Google to “move over” your content from the previous domain name to the new one, you’d better be prepared for some long haul redirection!
That’s right, don’t just give away, remove, or delete the old domain, as Google apparently scans these redirects for years on occasion.
It’s been said in SEO circles that 3 months of redirection is enough, but that seems to be an arbitrary figure that does not reflect what Google and its algorithm do in reality.
John Mueller of Google said that three months for a redirect is not enough and you really need to keep it up for a year at a minimum.
That puts companies such as Canvas in a pickle, as litigation forced them to move to a new domain name; their domain rebranding was quite unfortunate.
Long story short: Domain rebranding involves keeping the old domain, basically. Don’t dispose of it when you decide that the old brand needs a refresh!