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I'm comfortable with the steps of moving a site to a new domain name as recommended by Google. However, in this case, the domain name I'm asked to move to is not really "new" ... meaning it's currently hosting a website and has been for a long time. So my question is, do I do this in steps and take the old website down first in order to "free up" the domain name in they eyes of search engines to avoid large numbers of 404s and then (in step 2) switch to the "new" domain in a few months? Thanks.