10.2.700 Feature Summary references a Report Label Clean-Up Utility:
Report Label Clean-Up Utility
Use this new command line utility to exclude unused labels from report output.
By design, in the report server functionality you are limited to 1024 translatable labels being provided to an RDL.
Adding more labels results in error. If the number of labels on your custom report exceed the default limit, run
the Report Label Clean-up utility to analyze report usage patterns and automatically exclude unused labels from
the Report Data Definition (RDD). This will allow you to add your custom labels instead.
Where can I find this utility? Epicor Support doesn’t know anything about it but it sounds like it might be a nice little tool.