Deploying software and updates using Configuration Manager
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It seems you're trying to split the infrastructure so that each company has their own independent environment, you have a few options to consider.
One option is to create a new CAS server for each company and move one of the existing primary sites to each new server. Then you can configure trusts between the domains to maintain communication between the sites and ensure that each company can manage their own devices.
Another option is to remove the CAS entirely and have separate independent hierarchies for each company. This involves setting up a new primary site for each company and potentially migrating objects from the existing primary sites to the new ones.
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