if numExhaustedZones >= len(nt.zones) { // all zones are exhausted.
			return nodesList, errors.New("all zones exhausted before reaching count of nodes expected")
		}
		for zoneIndex := 0; zoneIndex < len(nt.zones); zoneIndex++ {
			na := nt.tree[nt.zones[zoneIndex]]
			if nodeIndex >= len(na) { // If the zone is exhausted, continue
				if nodeIndex == len(na) { // If it is the first time the zone is exhausted
					numExhaustedZones++
				}