I don't have Ubuntu Pro. Can you tell me what it is and how to update it? You can subscribe here: https://ubuntu.com/pro/subscribe When you click "Buy" at the bottom (I can't check what happens, since I've already did this years ago), but I believe that you get a token (a string of characters to copy), and the page tells you how to use it to enroll your machine. Once it's enrolled, do an update in the normal way with Software Updater. After everything is up-to-date, you get the offer to upgrade to 20.04. See attached screenshot from today, Jul 26.
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