[eluser]TheFuzzy0ne[/eluser]
It's experienced more often whilst developing, but you will probably find that you run into the same problem on your live server. By default, CodeIgniter does a 302 redirect, which instructs the browser that the page has temporarily moved, but it seems that browsers still seem to cache it. If you use a 307 redirect, it instructs the browser that the page has temporarily moved, so the redirect shouldn't be cached.