I've had my Ecobee for several years and it has been very reliable! I really hate cloud based stuff because this is what can happen and with little to no warning. If there is no path forward my next T-Stat will be local API based, possibly a Venstar CT, not sure on Z-Wave. The cloud API is returning 500s, during NS discover, which is not a good sign. https://api.ecobee.com:443 "GET /1/thermostatSummary?json=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx HTTP/1.1" 500 None