Dec 18
20
Google’s John Mueller said on Twitter that there is a delay currently with the notices that go out after a site has switched over the Google Mobile First Indexing. John said “We’re a bit behind with messaging of the mobile-first indexing because we’re switching to a model that reduces the number of messages owners of many sites get (currently in test, should be catching up in the next weeks, assuming all goes well 
).”
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Google Mobile First Indexing Notices Are Delayed Within Search Console