In some scenarios you may see that your query changes doe not reflect in the report. This is due to some caching that is done. The obvious thing is to delete the AUC files and clear out your data usage. But there is a new table that we need to be aware of in this scenario.
Navigate to the AOT and delete the SRSReportQuery table.
In table browser, you can only delete records that have the same user id (Note: you can only delete your records. You can not delete other users.).
The reason you don’t have permission is because the delete method was overridden to restrict this.
Below I wrote a job to delete them all with out hitting the delete trigger.
See the troubleshooting article on technet which briefly mentions this.