For long range tags, until now the system were automatically enabling "Low Power Receive Mode" when it determines the sensor tag is well within range and frequency drift is well within limit (so frequency calibration is not needed,) and disabling it when the signal strength drops or frequency drifts.
The Low Power Receive Mode works well only if the radio channel has been quiet (no user command to other tags) for at least 10 seconds prior to sending a command to the tag with the mode enabled. If immediately following a command to another tag, a command is sent to the tag, there will be longer than usual delay, even "tag did not respond" error.
Although this mode will increase stand-by battery life, we have determined that it should only be enabled if the user chooses to. Effective immediately the system will respect user's setting and will not attempt to automatically enable this mode. If you want to take advantage of this mode to increase battery life, and understand its above limitations, please enable this mode manually from "More..." > "Receiver Mode" (web interface) or "Gear icon" > "Receiver Mode" (iOS app).