This object records the UTC timestamp of an alarm's occurrence, or, if the alarm's perceived severity has since changed, the time of that most recent severity change. Admins rely on this field rather than alarmId to sort alarms into true chronological order, since the ID's rollover behavior at the Integer32 maximum makes it unsuitable for time ordering. For example, an alarm raised at 14:02 UTC that later escalates from minor to major at 14:15 UTC would show alarmEventTime as 14:15, not the original 14:02.