Let's say you want to migrate SSRS reports from an old reporting service server (e.g. SQL Server 2008 R2) to a new one (e.g. SQL Server 2016). What involves?
There are 3 steps:
Figure: Find reports creators by clicking "Details View" inside report folder
Figure: Send an email to ask permission
Figure: Email received with permission to delete from creator
Tip: Use the ReportSync tool to save time.
If audit results are exactly the same on old and new servers, it indicates that migration is successful.