For most Microsoft IT professionals, migrating or updating a native mode SQL Server Reporting Services (SSRS) installation from one version to another is a rare, if not once-in-a-lifetime, event – and probably one you would prefer a root canal to. Because software upgrades of all types tend to get postponed as long as possible, if you find yourself finally tasked with such an upgrade, several unpleasant things are likely true:
The effort is in crisis mode, driven by software (SSRS, OS) going off support, hardware becoming unreliable, or a line-of-business application that must itself be upgraded but cannot be until SSRS is.
The current installation was not done by you and whomever did is long gone, so you are not that familiar with it and would frankly rather not be. SSRS is not your “thing”.
The current installation is poorly documented, if at…