Selected answers from the Dumb SEO Questions G+ community.
W.E. Jonk: I see. What you can do is "fetch as Googlebot" in GWT . As far as I can see your home page (or /blog) should be successful. After you can submit to index. However it can take some time before the warning in your GWT will be removed. Therefore if you know the issue is fixed, relax because GWT is quite slow and not real-time.<br /><br /> ;
W.E. Jonk: GWT has a two/three days delay and since your Cache-Control was two days I wouldn't be surprised if this problem would disappear tomorrow or the day after. But I am guessing here, maybe someone else has a better point a view.
W.E. Jonk: People much smarter then me are going to look at this question this Thursday during the HOA. So let me cross-link so that they can look at the whole question at once:<br /><br /><br />
W.E. Jonk: I forgot to mention that you can re-submit the Sitemap in GWT. After you will see "pending" and after some time the Sitemap is re-submitted and maybe then the message will disappear. ;<br /><br />Reference: ;<br />