We usually use the following approach, in case you are using some cloud provider and have cloning functionality. So usually there is one production instance, however when you need to test some changes, then production instance is cloned and changes are tested on cloned version first, if everything is fine then same changes can be applied to the production instance. However there are some caveats, like stopping email/push queue and/or disabling cron, in case of remote storage some more actions needed.

UNA Cloud supports cloning as well with automatic change of hostname for cloned instance.