Before upgrading, PTC recommends you use Windchill Usage Assessment tool to address any inadvertent license usage. This ensures that your Windchill instance is properly licensed and is in compliance. The following flowchart provides the steps that need to be followed to assess the license usage.

You can download the Windchill Usage Assessment tool from this website on PTC Support site.

You can also refer the following article: https://www.ptc.com/en/support/article?n=CS277240 and Windchill Help Center for more information on Windchill Licensing.