# Batch delete > The CLI allows you to delete comments based on a time period, for example all comments older than two years. This is useful for cleaning up historical data. The CLI allows you to delete comments based on a time period, for example all comments older than two years. This is useful for cleaning up historical data. :::note The time period is based on the `timestamp` field of the comment, rather than the datetime the comment was uploaded to Communications Mining™. ::: :::note This section assumes that you have already installed and [configured the CLI](https://docs.uipath.com/ixp/automation-cloud/latest/cm-user-guide/configuring-the-cli#configuring-the-cli). ::: ## Backing up annotated data Before deleting or modifying your comments, you may optionally want to back up annotated comments, so as not to accidentally lose the manual work of the model trainers: ``` re get comments \ \ --dataset \ --reviewed-only true \ --file ``` If the source was added to multiple datasets, you should run the previously mentioned command for each of those datasets. ## Deleting Data :::warning Deleting annotations changes model performance. If the comments you want to delete were added to one or more datasets where they could have been annotated, deleting annotated comments will result in a change of model performance in those datasets going forward. Pinned models will be unaffected. Optionally, you can configure the CLI to skip annotated comments. ::: The following command deletes all comments in a source between `FROM_TIMESTAMP` and `TO_TIMESTAMP` , excluding annotated comments. The timestamp should be in [RFC 3339 format](https://datatracker.ietf.org/doc/html/rfc3339#section-5.8), e.g. `1970-01-02T03:04:05Z`. ``` re delete bulk \ --source \ --include-annotated=false \ --from-timestamp FROM_TIMESTAMP \ --to-timestamp TO_TIMESTAMP ``` If you are sure you want to delete annotated comments, you can set `--include-annotated=true`.