I just performed a server OS patch and deleted some old SolarWinds products, which caused all services to be re-installed, and then I rebooted the sever. . Like magic the scans all started running again. Still looking for a way to monitor/detect this...heading over the the APM template area..if not I may find a way to make one (using SQL/SWIS query or something) and upload it.
Edit: I found this IPAM_Delayed_Scan_Job.png by bluefunelemental and I "simplified" it for my usage and made it into a Orion web based report that gets sent to me daily instead of installing the SWIS API and making a template, etc. which seemed like overkill for now.
The query I am using is:
SELECT DISTINCT s.subnet.friendlyname as [SubnetName], queuetimestamp as [LastScan], tostring(HourDiff(queuetimestamp, getdate())) as [DelayedHours] FROM IPAM.ScanInstance s WHERE HourDiff(queuetimestamp, getdate()) > 4 ORDER BY [DelayedHours] DESC