I know there were tons of sites that got notifications that their sites migrated to the mobile-first indexing process this week. But Google is far from done. Google said currently sites being migrated are pretty equivalent on the desktop compared to mobile page side. John added in the hangout this morning that it still can take years for ALL sites to be migrated from desktop first indexing to mobile first indexing.
John said on Twitter yesterday that the sites moving over now are still being seen by Google as "mostly equivalent on desktop & mobile."
We do this on a per-site basis, and we notify you for the properties verified in Search Console. This is generally more of a neutral thing, but shifting over means your site is seen as mostly equivalent on desktop & mobile, which is great. More at https://t.co/tG5zTYYPoX
— 🍌 John 🍌 (@JohnMu) September 20, 2018
This site, the one you are reading, is still pretty old school with the mobile version of the site. It is not a responsive site and it has yet to be moved to the mobile-first indexing process and that makes sense to me.
John said in the hangout this morning at the 13:05 mark that he assumes over years that Google will want to shift everything over from desktop indexing to mobile-first indexing. It will take time as we covered before.
So sites that did migrate over, according to John, really should not see a shift in rankings because of being in mobile-first indexing at this point. The sites Google migrated over are current designed not to see such ranking shifts.
And if you were not yet migrated, no need to worry - you may want to consider making your pages more equivalent because it may be a sign that Google doesn't see your desktop and mobile pages to be in par. But for now, Google will continue to crawl the desktop version. That will however change at some point.
Forum discussion at Twitter.