We know that all new sites that have launched after July 1, 2019 would default to mobile-first indexing in Google's index. But what if you launched a brand new site on an existing old domain name that has not been switched to mobile-first indexing?
Google's John Mueller said no, that would not default to the mobile-first indexing. Google will have to access the new site when it detects it and make that assessment to move it over or not the way it does for sites launched prior to July 1, 2019.
John said on Twitter that on a simplistic level, Google "keeps a list of the domains that we feel aren't ready yet." So if that old domain is on that list, Google won't consider a relaunch on that domain as a new domain. It will of course eventually detect the new site and crawl it and automatically determine if the site is ready for mobile-first indexing. But it will not just remove it from the "sites not ready for mobile-first indexing list" because a new site was launched on it.
John said "If you launch a new site on an existing domain, it doesn't automatically change the status of the domain -- we'll still check to see if the domain overall is ready before removing it from that list."
Here are the tweets:
We basically keep a list of the domains that we feel aren't ready yet. If you launch a new site on an existing domain, it doesn't automatically change the status of the domain -- we'll still check to see if the domain overall is ready before removing it from that list.
— 🍌 John 🍌 (@JohnMu) August 18, 2020
This is one of those things that are "good to know" but really does not make a big practical difference.
Forum discussion at Twitter.
