The earliest calendar day any criterion could need, used to floor document retrieval.
Retrieval must widen to the union of every criterion while judging stays per-criterion — if the
agent narrows since to one window's start, documents the other criterion depends on are never
fetched, and the question fails for a reason invisible in the answer. Event-relative criteria have
no window, so their event day is folded in when it's known.
The earliest calendar day any criterion could need, used to floor document retrieval.
Retrieval must widen to the union of every criterion while judging stays per-criterion — if the agent narrows
sinceto one window's start, documents the other criterion depends on are never fetched, and the question fails for a reason invisible in the answer. Event-relative criteria have no window, so their event day is folded in when it's known.