Due to limitations with the Script Security Plugin such as https://issues.jenkins-ci.org/browse/JENKINS-43722 I have implemented a custom backup and restore mechanism which overwrites the scriptApprovals.xml on disk. The option "Reload Configuration from Disk" does not reload the script approvals and a full restart of Jenkins is required before the approvals lists are re-populated. This seems counter to the description of the option which states: "Discard all the loaded data in memory and reload everything from file system. Useful when you modified config files directly on disk."