diff --git a/backend/src/lib/booking-flow.js b/backend/src/lib/booking-flow.js
index e02dd97..5f3b5b1 100644
--- a/backend/src/lib/booking-flow.js
+++ b/backend/src/lib/booking-flow.js
@@ -89,6 +89,10 @@ export function classifyRoom(site, allBookings, viewDate, yesterday, tomorrow, o
   // Determine flow type
   let flowType = 'vacant'
 
+  // True when primaryBooking is a historical depart-only record (set below) rather
+  // than a booking that actually occupies viewDate — the room was vacant that night.
+  let isPastDepartureRecord = false
+
   if (primaryBooking) {
     const status = (primaryBooking.booking_status || '').toLowerCase()
     if (status === 'blocked') {
@@ -113,6 +117,7 @@ export function classifyRoom(site, allBookings, viewDate, yesterday, tomorrow, o
   } else if (effectiveDeparting && opts.past) {
     primaryBooking = effectiveDeparting
     flowType = 'depart'
+    isPastDepartureRecord = true
   }
 
   const arrivalDate   = primaryBooking ? toDateStr(primaryBooking.booking_arrival)  : null
@@ -158,7 +163,10 @@ export function classifyRoom(site, allBookings, viewDate, yesterday, tomorrow, o
     flow_type: flowType,
     booking:   primaryBooking,
 
-    spans_previous: isVacantFlow
+    // A past-departure record only marks that a checkout happened on viewDate — it
+    // never occupied the night before viewDate, so it must not merge with the prior
+    // card the way a booking that's still actively occupying viewDate would.
+    spans_previous: (isVacantFlow || isPastDepartureRecord)
       ? prevVacant
       : !!primaryBooking && !!arrivalDate && arrivalDate < viewDate,
     spans_next: isVacantFlow ? nextVacant : spansNext,