When I change a client description using the following code:
commcell = Commcell(commvault_server, authtoken=token)
client_name = 'cvclient001'
new_description = 'Test Client zero-one'
client = commcell.clients.get(client_name)
client_properties = client.properties
client_properties['client']['clientDescription'] = new_description
client.update_properties(client_properties)
I noticed that advanced settings changed from Another client group to This Object:
Settings before I ran the script:

After I ran the script (description was updated but also:

And in the audit trail report I saw:

I dont think that modifying a description should result in an extra Additional Setting.
Therefor I added an issue on github, but that isnt noticed (yet ?).