Only reservations trigger Smart Calendar rules.
If listing A is set to block listing B, and listing B is set to block listing C, a confirmed reservation on listing A will block listing B's calendar, but since this is not a reservation, it cannot trigger listing B's Smart Calendar Rules, and listing C's calendar will not get blocked. To block both listings, add them individually to listing A's Smart Calendar Rules.
Similarly, if listing A is set to block listing B, a manual calendar block on listing A will not trigger listing A's Smart Calendar Rules, and listing B's calendar will not get blocked.
