https://www.ikmultimedia.com/eligibilitycheck/index.php?a=sampletank-4-max
This page is designed to help confirm product eligibility to purchase different versions of a product.
Choose the main 'Product' name in the menu on the left, then from the right menu, select which 'Versions' you are interested in such as Upgrade, Crossgrade, or Maxgrade. All products that qualify you to purchase and register that Upgrade, Crossgrade, or Maxgrade product will then be displayed underneath.
The 2 drop-down menus are, in fact, one above the other.
You may well find it useful.
