I’ve been trying to figure it out for a few weeks, and I think I have a general answer. (but don't try to post a general answer in the general forums because it's apparently no mans land).

I have seen both orange and red “Manned Aircraft” notifications, and I believe that the orange notifications are a “Aircraft in the vicinity above 400’AGL but less than… 1000’ (maybe on that number), and that the red notifications are aircraft flying at or below 400’AGL.

I havent seen the blue notifications that are there, but I believe those would be well above 1000’ AGL such as a commercial passenger jet approaching an airport over 25SM away.

Does anyone else have any insight?

I have only seen red ADS-B warnings and have no idea what altitude the aircraft were flying at.  Sorry, wish I could have been of more help.

The thing is that it is working.

Niknik Posted at 10-16 14:40
The thing is that it is working.

But is it working if it doesn't actually provide usable data that one can understand the associated risk?

In my experience, the aircraft that are of the biggest concern (low altitude) are usually small local aircraft that aren't broadcasting ADS-B signals.  Its usually only the large aircraft flying way higher than a drone operates at which are broadcasting an ADS-B signal.