Edit or Delete a Standard schema.

I have a HL7 schema listed within Healthshare that is marked as 'Standard' however this doesn't appear to not a standard schema and more of a custom one created (there are very specific Z segments within it) that has somehow been marked as a standard. Is there a way to change it from a Standard to Custom? I realise that this cannot be completed within Healthshare but is there a way to change this within Studio?

Thanks