Lol they're HTTPS on the login form but plain HTTP immediately after... what a joke? That invites people to do cred fishing on bigger LAN parties or conferences...
It took me a minute of browsing around the site and then coming back here to ask, before I realized that you're saying they're redirecting httpS to PLAIN http. Wow.
I've actually seen it a few times myself but I don't have any examples offhand. My company's filter is lazy so it doesn't filter https traffic. Sometimes if I get a blocked site that's http I try the URL with https instead. Once in a while I get a redirect to http.