This disclosure describes an operational mode of a telemetry module. A device, such as a programming device, operating in accordance with the techniques of this disclosure determines that a transceiver of an implantable medical device is operating in a duty cycled operational mode that includes at least one interval during which the transceiver is powered down interleaved with intervals during which the transceiver is powered up, e.g., for transmitting or receiving communications over an established communication session. The programming device is configured to transmit information during the at least one interval in which the transceiver of the implantable medical device is powered down. Doing so ensures that the channel over which the programmer and implantable medical device communicate will not be usurped by another device.