NFS Export Rules Update

Anyone using VMware vRO and it's ViPR controller plugin to create/modify NFS?  Need to be able to alter existing rules to add IPs for access.  Basically if I rerun the export workflow, I get the following:

[2017-04-01 10:42:29.195] Error in (Dynamic Script Module name : init#383) Error: Filesystem export failed with error: Error 1013: File System has existing export. To modify the export and its rules, please use update URL.

[2017-04-01 10:42:29.229] Workflow execution stack:

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item: 'Export EMC ViPR File System/item1', state: 'failed', business state: 'null', exception: 'Error: Filesystem export failed with error: Error 1013: File System has existing export. To modify the export and its rules, please use update URL.  (Dynamic Script Module name : init#383)'

Thanks for any insight.