This read-write integer, from 1 to 12, sets the fixed calendar month in which annual (non-recurring-rule) Daylight Saving Time begins on the switch. An administrator uses this variant instead of the repeating-rule objects when the local DST schedule is defined by a fixed date each year rather than a "Nth weekday" rule. For example, a jurisdiction with a legally fixed DST start date would configure agentDSTAnnualStartMonth alongside agentDSTAnnualStartDayOfMonth rather than the repeating start objects.