For reference's purpose, this topic is actively discussed in the OME board under OME 3.8.0 API dropping devices.  I have confirmed that /api/DeviceService/Devices listing drops the device's ID whenever the device is rebuilt with a new name.  If you want to read more, go to the other topic.  I'll close this one.
As I ingest from OME Version 3.8.0 (Build 35) using DeviceService/Devices every day, I notice that the number of devices returned from this interface diminishes nearly monotonically.  After four months, I'm getting <80% of initial count.  I can verify that most, if not all devices in the missing list are visible in the UI and correctly inventoried.  The missing device would not reappear in DeviceService/Devices even after inventory rerun. How can I get complete devices list? (Also, why missing devices grow?)
OME API's DeviceService/Devices missing devices