SanDiegoRep - The system is running on Essentials 7.6. I'm surprised because this 8ANS activated and transferred successfully many times before. And it's sitting in a 4-gang box with 2 other devices that have never failed to activate or transfer.
And new news - Before these failures started happening, I added an Event via the iPad app that turned this device on at sunset and off several hours later. For the last two nights, I've had to turn the device on manually (at the switch) and it turns off automatically per the event schedule. Go figure...