Webmasters this morning received notification from Google saying that their implementation of hreflang on their website was flawed. The notification reads as follows:
Google had detected that some pages on your site have implemented the rel-alternate-hreflang tag incorrectly. In particular, there seems to be a problem with incorrrect language and region codes, or incorrect bi-directional linking (if page A links with hreflang to page B, there must be a link back from B to A as well). Google uses the hreflang attributes to serve the correct language or regional URL to the right users in search results.
Until you correct the errors on the hreflang links, your website will not benefit from additional language or region targeting.
Gary Illyes confirmed that such notifications were being sent out, and the exact number of them would be given out later. He claims that 15% of them were being sent due to the mobile applicability issues seen on web sites.
If on the receiving end of such a notification, then issue needs to be fixed, so that advantage can be take of the ‘additional language or regional targeting’ that hreflang offers. It’s possible it’s a mass notification being sent out due to detection of common implementation errors.Hreflang Implementation Flawed, Says Google Search Console To Webmasters!,