There is a certain amount of confusion related to updating or upgrading Studio One and most of it is based on how software applications historically have handled that process. In that regard, it leads users to often take unnecessary steps at times when updating or upgrading.
1. Studio One does not patch updates or upgrades. Every new major or minor version is a full install. If you move from 3.1.1 to 3.1.2, download and install 3.1.2. The same goes for any minor or major update.
2. The different versions, Demo, Prime, Artist, Professional, are all the same software underneath, platform dependent. For example, Studio One Windows x86 and x64 are two different installers, but underneath it's all the same and it contains all of the versions. It's only the license that determines what version launches. Changing from Prime to Professional or anything similar of the same release version (3.1.1 Prime to 3.1.1 Artist) only requires activating the new license, there's no need to download and re-install the application.
Once you understand the basic philosophy, that it's mostly all based around the license, those changes are much easier.
Additional Notes: One of the single largest issues with activation is because many users create multiple user accounts. For example, a user will own Studio One 3 Artist, but activate the Studio One 3 Demo or Prime version in another different user account. This creates confusion because products can only be activated from the accounts they exist in and often creates additional issues with the computer keychains that store those passwords. If you are running Prime from account B and own Artist in account A, you won't be able to activate an upgraded license for Artist while signed into account B.
In that regard, please try to keep all of your Presonus software products in a single user account which will help to reduce random activation issues.