A network device establishes a depth-aware communication schedule for one or more nodes in a data network having a routing topology comprising a root node, the establishing including selecting from a slotframe of the depth-aware communication schedule a first subset of timeslots based on the depth, and allocating to each timeslot in the first subset an exclusive role (a transmit operation, a receive operation, or an idle state) for one or more of the nodes at the corresponding depth; the network device identifies one or more idle states in the depth-aware communication schedule, and selects a second subset of timeslots from the idle states as in-case-of-emergency timeslots, based on the network device identifying in the second subset a corresponding timeslot at a neighboring depth being allocated a corresponding transmit operation or receive operation; the network device causes selective transmission of a prioritized data packet in an allocated in-case-of-emergency timeslot.