So the refresh is completely dependent on the repository. When metrics are updated or created in apps before their ownership can be changed a reference needs to exist in the repo. GMS gets notified of the repo changes but the changes can take some time depending on volume and other repo operations going on at the same time. As for the test page master items toggle, it's not meant to be a real-time view as updates happen. The purpose of the master items toggle is to grab ids for previously generated metrics so you can update your source data to handle the changes that came with the introduction of MLS and the governed metrics application.