This is a text timestamp recording exactly when one specific, already-completed 15-minute collection interval, retained in a rolling history buffer so a series of past intervals can be graphed began collecting its ingress traffic on this service classified as accepted (in-profile), yellow (remarked, over the committed rate but under the excess rate), or dropped (over the excess rate), plus live receive-rate gauges. On this element it is the anchor you need before trusting any of the accompanying ingress rate-policing counters reported alongside it in this same bin, since without it you cannot tell whether a given count covers a completed 15-minute window (for example 14:30-14:45) or some other span entirely. For example, a start time of 2026-08-06 09:15 on this History bin tells you every ingress rate-policing counter reported with it only reflects activity from that moment forward, not anything that happened earlier.