Temporal (calendar-driven)

Examples. Birthday offers. Holiday coupons. End-of-school promotions.

Technical approach. Scheduled jobs triggered on calendar events rather than user behavior. Distinct from the user-activity-driven tiers above because the signal itself is exogenous; latency is measured from the calendar event, not from a user action.

Why it deserves its own tier. Temporal activations have different consent/preference dynamics — they're not reactive to user intent and so are more sensitive to fatigue and unsubscribe risk.