https://www.bleepingcomputer.com/news/microsoft/how-to-get-more-time-to-uninstall-windows-10-feature-updates/

By default, Microsoft allows users ten days to uninstall a new Windows 10 feature update and roll back to a previous version of the operating system. In this article, we will show you how to increase your 'OS uninstall window' to give you more time to test out a new Windows 10 feature update.

After installing a new Windows 10 feature update, it is not uncommon to run into bugs, performance issues, or crashes that require you to uninstall the feature update until the bugs are fixed.