Systems and methods optimize broadcast transmissions from a parent device operating on a time-slotted channel hopping (TSCH) network to one or more low-energy endpoint devices connected and synchronized to the communications of the TSCH parent device. As part of a Receiver Initiated Transmit (RIT) communication process, the TSCH parent device receives a check-in communication from a connected low-energy endpoint device during a wake state of a wake/sleep cycle of the low-energy endpoint device. In response to the check-in message, the TSCH parent device transmits an acknowledgment message identifying a broadcast timeslot during which the TSCH parent device will broadcast stored broadcast messages. During the identified timeslot, the TSCH parent device broadcasts stored broadcast messages to any connected low-energy endpoint devices that are tuned in to the corresponding frequency channel according to the TSCH protocol.