Since it's so hard to find right now, I thought I'd post the right web page for updates. It seems many people got directed to the wrong page. And sometime today (I think) a direct link via a button on the Logos home page disappeared, leaving only a button that gives you full price.
Here's the correct web page to see what discounts Logos believes you are entitled to:
http://www.logos.com/upgrade
If you don't mind, if others from around the world bump this once in a while, it will stay visible for those who are not getting to the right page.