diff --git a/backend/handlers/scheduling/default-hours.go b/backend/handlers/scheduling/default-hours.go
index bdfde58..5a4a24c 100644
--- a/backend/handlers/scheduling/default-hours.go
+++ b/backend/handlers/scheduling/default-hours.go
@@ -275,6 +275,11 @@ func GetAvailableHours(w http.ResponseWriter, r *http.Request) {
 		log.Printf("Failed to cleanup old reservations: %v", err)
 	}
 
+	// Anonymize stale guest accounts (6+ months after last booking)
+	if err := AnonymizeStaleGuestAccounts(r.Context()); err != nil {
+		log.Printf("Failed to anonymize stale guest accounts: %v", err)
+	}
+
 	// Load default hours
 	defaultMap := map[int]DefaultHours{}
 	defRows, _ := db.DB.Query(r.Context(), `SELECT weekday, start_time::text, end_time::text, is_open FROM working_hours`)
@@ -456,21 +461,21 @@ func GetAvailableHours(w http.ResponseWriter, r *http.Request) {
 					day.Slots = subtractTimeSlots(day.Slots, dayBlockers)
 				}
 
-		// Late night lock: after 22:00, block next morning 00:00-11:00 for non-admin users
-		now := time.Now()
-		if !isAdmin && now.Hour() >= 22 {
-			// Check if this is tomorrow's date
-			tomorrow := now.AddDate(0, 0, 1)
-			tomorrowStr := tomorrow.Format("2006-01-02")
-			if day.Date == tomorrowStr {
-				// Add a fake blocker for 00:00-11:00
-				lateNightBlock := TimeSlot{
-					StartTime: "00:00",
-					EndTime:   "11:00",
+				// Late night lock: after 22:00, block next morning 00:00-11:00 for non-admin users
+				now := time.Now()
+				if !isAdmin && now.Hour() >= 22 {
+					// Check if this is tomorrow's date
+					tomorrow := now.AddDate(0, 0, 1)
+					tomorrowStr := tomorrow.Format("2006-01-02")
+					if day.Date == tomorrowStr {
+						// Add a fake blocker for 00:00-11:00
+						lateNightBlock := TimeSlot{
+							StartTime: "00:00",
+							EndTime:   "11:00",
+						}
+						day.Slots = subtractTimeSlots(day.Slots, []TimeSlot{lateNightBlock})
+					}
 				}
-				day.Slots = subtractTimeSlots(day.Slots, []TimeSlot{lateNightBlock})
-			}
-		}
 			} else {
 				// Admins: keep blockers visible for warning display
 				if dayBlockers, ok := blockerMap[day.Date]; ok {
diff --git a/backend/handlers/scheduling/time-blockers.go b/backend/handlers/scheduling/time-blockers.go
index 7454fa5..1036090 100644
--- a/backend/handlers/scheduling/time-blockers.go
+++ b/backend/handlers/scheduling/time-blockers.go
@@ -336,6 +336,8 @@ func CheckTimeBlockerOverlap(ctx context.Context, startTime, endTime time.Time)
 // CleanupOldReservations deletes expired reservations:
 // - Logged-in (RESERVATION:user): older than 1 hour
 // - Anonymous (RESERVATION:anon): older than 10 minutes
+// - Admin walk-in (RESERVATION:admin:walkin:%): older than 10 minutes
+// - Admin call-in (RESERVATION:admin:callin:%): older than 1 hour
 func CleanupOldReservations(ctx context.Context) error {
 	oneHourAgo := time.Now().Add(-1 * time.Hour)
 	tenMinutesAgo := time.Now().Add(-10 * time.Minute)
@@ -344,6 +346,36 @@ func CleanupOldReservations(ctx context.Context) error {
 		DELETE FROM time_blockers
 		WHERE (description LIKE 'RESERVATION:user:%' AND created_at < $1)
 		   OR (description LIKE 'RESERVATION:anon:%' AND created_at < $2)
-	`, oneHourAgo, tenMinutesAgo)
+		   OR (description LIKE 'RESERVATION:admin:walkin:%' AND created_at < $2)
+		   OR (description LIKE 'RESERVATION:admin:callin:%' AND created_at < $3)
+	`, oneHourAgo, tenMinutesAgo, oneHourAgo)
+	return err
+}
+
+// AnonymizeStaleGuestAccounts anonymizes personal data for guest accounts
+// whose last booking was more than 6 months ago (UK GDPR storage limitation).
+// Financial records (bookings, payments) remain intact — only PII is scrubbed.
+// Active/pending bookings are excluded so the salon can still contact the guest.
+func AnonymizeStaleGuestAccounts(ctx context.Context) error {
+	_, err := db.DB.Exec(ctx, `
+		UPDATE users SET
+			n_first_name = 'Guest',
+			n_last_name = 'Anonymized',
+			email = 'anon-' || id || '@anon.invalid',
+			phone = '000000000000',
+			date_of_birth = '1900-01-01',
+			updated_at = NOW()
+		WHERE account_role = 'guest'
+		  AND id NOT IN (
+			  SELECT user_id FROM bookings WHERE status IN ('pending', 'confirmed')
+		  )
+		  AND id IN (
+			  SELECT user_id
+			  FROM bookings
+			  WHERE user_id IS NOT NULL
+			  GROUP BY user_id
+			  HAVING MAX(start_time) < NOW() - INTERVAL '6 months'
+		  )
+	`)
 	return err
 }