The old Reports Module is obsolete, though it is still shipped with XAF to provide compatibility with legacy XAF applications. While we do not urge or request that our clients migrate their existing solutions to the new ReportsV2 module immediately (since the former module is valid and can be used in existing apps), we do recommend using the new Reports V2 Module module for new projects. You can also use ReportsV2 and the previously available Reports modules within the same application if you want to maintain use of existing reports along-side of new reports generated with XAF's ReportsV2 module.
Take special note that supporting the old module required and continues to require our resources (which are taken from new features), because dealing with the new IDEs/.NET versions is costly (not to mention changes in the underlying components). It was thus far not critical for our team to think about the removal date at this stage, but we will see how it goes in the future. So, you must definitely plan this migration for the future, but it is not that urgent. When we decide on the date with our management, we will surely communicate these plans to our customers in advance before their projects stop compiling.
To switch to the Reports V2 in your existing application, follow one of the approaches detailed below: https://www.devexpress.com/kb=T515516