You can now select the next status code using the Available Next Status Codes field. It will show the statuses that can be set as the next status.
You select the text in the field and it will open the list, from which you can select the status.
If there is only one status available in this field, selecting it will automatically set it as the current status.
In case when the next available statuses are not set up or if the Status Code field is empty, then the Available Next Statuses field will have Any Status value, which means that you can choose from the whole list of status codes.