I was able to modify virtualization-domain and port in the above URL format via alfresco-virtserver.properties.
How do I change the URL, so that I can change the virtual-hostname and www–sandbox fields?
BTW - just an outside info - the reason I am trying to change the Preview URL is - I am trying to open the preview URL from the Weblogic Portal Server, which actually points to the mounted CONTENT published from Alfresco.