Does anyone know what this could relate to?

I logged into Webmaster Tools to be greeted by this warning:
Attachment 6667
I don't see any warnings elsewhere except for a couple regarding my sitemap, which relates to robot text blocking the Author pages. Could it be that? I didn't want the author pages published, and robots have been blocked for a long time from those.

Google had me worried, but it's just the new search console telling me about the Author page that I blocked!

I get these for pages that i have set for no index

Yes, got the same mails in the past.

When you block a folder in robots.txt, they send you that email.