Sitemap without date?

My blog overview page is autogenerated using org-publish. Other pages are also autogenerated, but have a post template with #+DATE in them. This date gets pulled and inserted in the generated HTML as pubdate which is then used for the generation of RSS.

So after chaning the layout of the site, I figured out that the overview page is not aligned the same way as other pages are. The title of the sitemap is higher up then other pages. It took me some time to figure out why this is.

The autogenerated sitemap doesn't have #+DATE in it, so no pubdate can be inserted in the HTML of this page. That is why one line is missing on this page and the title is not aligned any more.
So I wrote a new function insert-pubdate (take a look at my config) that inserts the current date of the publication in the generated sitemap HTML. Now everything is aligned again.