Create Sandboxes in pre-release orgs

Why the Sandbox Enters a Stopped Status

The pre-release instance (GS0) is upgraded before all of the sandbox instances, during that time gap there are no valid destinations for copies that are submitted so the copies stop. It is not possible for Support to direct the sandbox request to an instance that will allow it to complete processing during that time.  Once the release preview goes out to sandboxes you may request for the copy to be resumed.

Steps to Resume the Sandbox Copy

Once the Salesforce release preview has been deployed to sandbox instances, request that Support resumes the sandbox copy process. No action is required during the gap period.