I have a pair of automations configured in iOS 10's Home app. One turns on some lights at sunset, the other turns them off at sunrise. Most days they run correctly. Some days one or the other will fail to execute. Doesn't matter if I'm home or away. I have two Apple TV 4's running tvOS 10 - both are correctly configured and allow me to access my HomeKit devices out of the house, so I know they're working (and are properly recognized in the Home app). Another program that turns on my bedroom lights daily at 6:20am (to wake me up for work) works perfectly each day. Any thoughts?