The button at the bottom of the subscription tab is fancier than it needs to be and causes confusion in the real world. The text on the button changes based on the plans available. Mine usually says "Update / Donate". However from my users point of view they are renewing not upgrading. The system has it's definition that if you are changing from one plan to another it is an upgrade but in the case of obsoleting one plan and replacing it with a new one (different price) to the users it is a renewal. The fact they click on a different plan from the one they are currently subscribed to doesn't mater to them, they are there to continue their membership. It didn't seem like a button that said "Upgrade" when renewing was that big of deal but after getting several complaints from confused people, I finally installed the English language pack so that I could change the text but as the final text on the button is dynamically generated it complicated what I could do. I finally changed the "upgrade" text to say "Renew / Upgrade" which makes my button now very long and says "Renew / Upgrade / Donate". It would actually be better if the button text was not dynamic and was much more generic such as "Next", "Submit", or "Continue"