I was under the impression the hub checks the model and current firmware and it then decides if it has a later version. At least, that's the way it seems to be explained
"The manufacturer, model ID and existing firmware of the device is inspected and if a match is found with a newer firmware version, then the device is updated, otherwise we bail with a log entry that the device is up to date"
From another thread:
"correct, we do not have any files for those manufacturers."
