You can easily move your service instance from one identity domain to another so long as both identity domains are in the same data center.
Occasionally, whether due to errors made when originally subscribing to a JCS-SaaS Extension service instance or, in the case of a SaaS application, when that application and the service instance were provisioned in different identity domains, you might need to move your service instance from one identity domain to another. If you are the service administrator, you can do this easily with the Identity Domain Administration’s Relocate Service feature.
These procedure for relocating an instance to a different identity domain apply only to instances provisioned prior to August 2017.
In the new Entitlement model, instances are not created by default. Instead, you provision APEX in the Dashboard first, then associate the APEX instance with JCS-SaaS Extension.