esaProbeStatsOutOfSeqErrs is a 64-bit performance counter counting packets that arrived with a sequence number less than or equal to the last one seen, for the interval that is still being actively collected (the live bin); it does not apply to Y.1731 probes. Out-of-order arrivals point to a reordering issue in the path, such as load-balanced links delivering packets on different latency routes, which a technician needs to separate from genuine packet loss before assigning a root cause. For example, if this live counter rises but the lost-packet counter in the same bin does not, the technician suspects a load-balancing or multipath reordering issue on the live circuit rather than dropped traffic.