The one at the top of https://stats.wikimedia.org/EN/Sitemap.htm, in addition to only sending people to previous round, is probably not as effective as it focuses on the May 2016 date.
Topic on Talk:Wikistats 2.0 Design Project/RequestforFeedback/Round2
Sadly the banner is dynamically generated and present on hundreds of pages, so it's hard to change manually. And Erik is on leave, and we don't know how to re-build Wikistats with the old perl scripts without messing things up.
I just checked, the banner is present on 17000+ pages (dynamically generated).
That's ok. I probably only really meant the main "Statistics per Wikimedia project" ones. But you know that if you need more people we can find different ways to make it happen.