diff --git a/backend/src/routes/tasks.js b/backend/src/routes/tasks.js
index 76795a7..2e5ce88 100644
--- a/backend/src/routes/tasks.js
+++ b/backend/src/routes/tasks.js
@@ -44,12 +44,24 @@ function classifyBookingStatus(rawStatus) {
 
 async function fetchRoomOccupancy() {
   const today = new Date().toISOString().slice(0, 10)
-  const bookings = await fetchBookings(today, today)
+  const yesterday = new Date(Date.now() - 86400000).toISOString().slice(0, 10)
+  // Query yesterday..today, not just today: a booking that arrived yesterday and
+  // hasn't checked out yet must still show as occupied. Don't trust NewBook's
+  // period_from/period_to filter to do that overlap server-side (hvac's scheduler
+  // learned the same lesson — see its lib/scheduler.js) — fetch the wider window and
+  // filter locally against each booking's own arrival/departure dates instead.
+  const bookings = await fetchBookings(yesterday, today)
   const occupied = new Set()
   const arriving = new Set()
   for (const b of bookings) {
     const siteId = b.booking_site_id ?? b.site_id
     if (siteId == null) continue
+    const arrival = String(b.booking_arrival ?? '').slice(0, 10)
+    const departure = String(b.booking_departure ?? '').slice(0, 10)
+    // Only bookings whose stay actually covers today belong in either bucket — the
+    // wider window also pulls back yesterday's now-departed booking, which shouldn't
+    // count towards either set.
+    if (arrival > today || departure < today) continue
     const id = String(siteId)
     if (classifyBookingStatus(b.booking_status) === 'occupied') occupied.add(id)
     else arriving.add(id)
@@ -96,7 +108,7 @@ export async function taskRoutes(app) {
     if (q.unoccupied === 'true') {
       let occupied
       try {
-        occupied = await fetchOccupiedSiteIds()
+        ({ occupied } = await fetchRoomOccupancy())
       } catch (err) {
         return reply.status(502).send({ error: `NewBook error: ${err.message}` })
       }