Hello
What I do is open up the developer tools on my browser, dump the rest call into a script and then pass it a list of all the ldev's I want to unprotect.
Here is a 'sample' video on how to do it using powershell, using lun creation as a sample, but you can do the same using method:
https://youtu.be/a4CCpywCbiUAlternatively if they are all in protector you can easily mass select them in protector and break the replication and delete the secondary volume[Button next to the high-lighted volume]. After that you can clean up the primary volume in administrator if need be. Screenshot below:

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William Jansen van Nieuwenhuizen
Hitachi Vantara
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