Last week, we got fourth batch of notices about the Google mobile-first indexing. A number of notifications were received related to the sites those were moved over to the mobile-first index, but it was found that none of those moved over sites are mobile-first, like the previous batches. The above said issues need to be explained here:
If those batches are to be dated, they would fall on these dates:
March: Batch one was a small subset back in March
April 30, 2018: the second batch, but was way more wide spread
May 17, 2018: the third batch of notices
May 27, 2018: the fourth batch of notices
Joost de Valk from Yoast, the SEO firm also noticed the same that a number of sites have got this fourth batch of notices:
See the forum discussion at Twitter.