First, let me say that I love Channels on AppleTV and I’m incredibly impressed by the responsiveness of the developers. I do have a feature request though.
I had a situation the other day where an AppleTV didn’t release a HDHomeRun tuner. I really didn’t know about this until I tried to watch something remotely via the iOS app and didn’t have a free tuner. As far as I could tell at the time, only one AppleTV/Channels instance was using a tuner. I ultimately discovered the tuners.html API on the HDHomeRun, and by process of elimination elimination, figured out the problem. One AppleTV had two IP reservations on my router. Rebooting the router, didn’t release the IP address or the HDHomeRun tuner. Unplugging the AppleTV didn’t either. Simply turning on the AppleTV and then back off did though.
The HDHomeRun is in a structured wiring panel, so just looking at the lights on the device isn’t that easy. It is simple enough to check http://x.x.x.x/tuners.html on the HDHomeRun, but it would be nice if the Channels app also displayed this information. That would make it a bit easier to notice when a tuner may be in use unknowingly.