This read-only Counter64 counts the number of times this PM instance timed out waiting for the router to send its next query. A growing count is an early warning that the upstream multicast querier has gone silent or died, which — left unresolved — eventually ages out all group membership on the port; because it is drawn from the current, still-open 24-hour bin for today, the number keeps climbing until midnight rollover, so it should be read as "so far today" rather than a finished daily total. On an uplink toward the multicast-enabled core router, a count of 2,550 over today so far is the kind of number an admin would trend against the join/leave rate on the same port to judge whether it's normal channel-surfing or an anomaly worth a closer look.