1. Hotfixes specifically designed for older version (e.g. 13.3.1) will no longer work in newer version (e.g. 13.4).
2. Re-applying those older versions hotfixes (e.g. 13.3.1) on newer version (e.g. 13.4) may break the installation.
3. User should check the release note of the newer version upgraded.
Click Here to access the release note of various versions.4. If those hotfix issues (e.g. for 13.3.1) have already been included and fixed in the newer version (e.g. 13.4), user would no longer need to apply those hotfixes after upgrade.