diff --git a/seaweed-volume/src/storage/store.rs b/seaweed-volume/src/storage/store.rs
index 56f58aaae..ea3da0104 100644
--- a/seaweed-volume/src/storage/store.rs
+++ b/seaweed-volume/src/storage/store.rs
@@ -2483,6 +2483,52 @@ mod tests {
         assert_eq!(selected, Some(0));
     }
 
+    // VolumeCopy picks a disk before deleting the replica it replaces, so only
+    // the location actually holding that replica may count its slot as free.
+    #[test]
+    fn test_find_free_location_predicate_credits_only_the_holding_location() {
+        let tmp1 = TempDir::new().unwrap();
+        let dir1 = tmp1.path().to_str().unwrap();
+        let tmp2 = TempDir::new().unwrap();
+        let dir2 = tmp2.path().to_str().unwrap();
+
+        let mut store = Store::new(NeedleMapKind::InMemory);
+        for dir in [dir1, dir2] {
+            store
+                .add_location(
+                    dir,
+                    dir,
+                    1,
+                    DiskType::HardDrive,
+                    MinFreeSpace::Percent(0.0),
+                    Vec::new(),
+                )
+                .unwrap();
+        }
+        for vid in [81, 82] {
+            store
+                .add_volume(VolumeId(vid), DiskType::HardDrive, &VolumeSpec::default())
+                .unwrap();
+        }
+        let loc_of = |vid| store.find_volume(VolumeId(vid)).unwrap().0;
+        assert_ne!(loc_of(81), loc_of(82), "fixture must fill both locations");
+
+        let hdd = |loc: &DiskLocation| loc.disk_type == DiskType::HardDrive;
+        assert_eq!(store.find_free_location_predicate(hdd, None), None);
+        assert_eq!(
+            store.find_free_location_predicate(hdd, Some(VolumeId(99))),
+            None
+        );
+        assert_eq!(
+            store.find_free_location_predicate(hdd, Some(VolumeId(81))),
+            Some(loc_of(81))
+        );
+        assert_eq!(
+            store.find_free_location_predicate(hdd, Some(VolumeId(82))),
+            Some(loc_of(82))
+        );
+    }
+
     #[test]
     fn test_delete_expired_ec_volumes_removes_expired_entries() {
         let tmp = TempDir::new().unwrap();