We've had several reports of Scheduled Jobs not being listed. In some cases this followed an upgrade. With other instances we can't be sure. Engineering has provided a fix with 2.8.3, which is still several weeks away. The fix addresses an issue related to the configuration of Auto Discovery jobs. As soon as you configure such jobs you will see no jobs listed on the Targets --> Scheduled Jobs page. The list will be listed again if the Scan Profiles, on the Targets Discovery page, is edited so that the Scan Frequency is set to Not Scheduled. If this does not work for you please open a ticket with Support.