This issue has been resolved.

The issue caused sensors and measurements from newly discovered devices to be missing from the user interface. All new sensors have been processed and should be visible in the user interface.
Existing sensors and their measurements were unaffected.

processing is back to normal.

A fix has been implemented and we are monitoring the results.

Our data processing infrastructure is running behind which is causing inaccuracies in the data shown.
No data has been lost and the system should catch up shortly.