Changes made to a project may impact reports already created using packages from the model, especially if query item names are changed or removed.
Adding new items to your model will not affect any existing reports that are based on packages from the model; however, if you rename or delete a query item from your model then any reports created using those items will no longer be valid because the query item is no longer part of the model package. Before republishing a package, you can see if any changes you have made to your model will affect any existing reports that use the package. You can find all of the changes that have been made to the package in the current session, as well as see details for each change and find out the names of reports affected by a specific change.