du-config.json: redundant manufacturer and model

[D-r-P-3-p-p-3-r]

What is the difference between manufacturer/model and _agents.manufacturer/agents.mode_l in the du-config.json? Why do we need to separate pairs? Why would the values for manufacturer and model ever be different between the two pairs?

I have figured out by trial-and-error that the values under agents are used to match against compatibility.manufacturer, and _compatibility.mode_l from the import/update manifest.
I also figured out that the top-level pair shows up under properties.reported.deviceInformation. The pair from the agents section shows up under reported.deviceUpdate.agent.deviceProperties.

But I have no explanation for the seemingly redundant configuration.