diff --git a/internal/topdata/native.go b/internal/topdata/native.go
index fd7f29a..d0139a4 100644
--- a/internal/topdata/native.go
+++ b/internal/topdata/native.go
@@ -4339,6 +4339,15 @@ func updateOverrideRowKey(datasetName string, row map[string]any, expanded map[s
 		}
 		return changed, retiredKey, nil
 	}
+	if oldKey == newKey {
+		row["key"] = newKey
+		rowByKey[newKey] = row
+		if _, ok := lockData[newKey]; !ok {
+			lockData[newKey] = rowID
+			changed = true
+		}
+		return changed, "", nil
+	}
 	conflictingID := -1
 	if conflicting, ok := rowByKey[newKey]; ok && conflicting != nil {
 		var conflictingHasID bool
diff --git a/internal/topdata/topdata_test.go b/internal/topdata/topdata_test.go
index 7c22b86..2a745f7 100644
--- a/internal/topdata/topdata_test.go
+++ b/internal/topdata/topdata_test.go
@@ -8776,6 +8776,80 @@ func TestBuildBaseitemsSplitReaddsRetiredKeyToLockfile(t *testing.T) {
 	}
 }
 
+func TestBuildBaseitemsAllowsKeyOnlyOverrideBeforeSameKeyIsRelocatedAndReadded(t *testing.T) {
+	root := testProjectRoot(t)
+	mkdirAll(t, filepath.Join(root, "topdata", "data", "baseitems", "modules", "10_vanillaoverrides"))
+	writeFile(t, filepath.Join(root, "topdata", "base_dialog.json"), "{}\n")
+	writeFile(t, filepath.Join(root, "topdata", "data", "baseitems", "base.json"), `{
+  "output": "baseitems.2da",
+  "columns": ["label", "MaxRange"],
+  "rows": [
+    {"id": 58, "key": "baseitems:shortspear", "label": "shortspear", "MaxRange": "100"}
+  ]
+}`+"\n")
+	writeFile(t, filepath.Join(root, "topdata", "data", "baseitems", "lock.json"), `{"baseitems:shortspear":59}`+"\n")
+	writeFile(t, filepath.Join(root, "topdata", "data", "baseitems", "modules", "10_vanillaoverrides", "ovr_baseitems_maxranges.json"), `{
+  "overrides": [
+    {
+      "key": "baseitems:shortspear",
+      "MaxRange": "255"
+    }
+  ]
+}`+"\n")
+	writeFile(t, filepath.Join(root, "topdata", "data", "baseitems", "modules", "10_vanillaoverrides", "ovr_baseitems_spear.json"), `{
+  "overrides": [
+    {
+      "id": 58,
+      "key": "baseitems:spear",
+      "label": "spear"
+    }
+  ]
+}`+"\n")
+	writeFile(t, filepath.Join(root, "topdata", "data", "baseitems", "modules", "add_baseitems_shortspear.json"), `{
+  "entries": {
+    "baseitems:shortspear": {
+      "label": "shortspear",
+      "MaxRange": "255"
+    }
+  }
+}`+"\n")
+	mkdirAll(t, filepath.Join(root, "reference"))
+	writeFile(t, filepath.Join(root, "reference", "build.py"), "print('ok')\n")
+
+	result, err := BuildNative(testProject(root), nil)
+	if err != nil {
+		t.Fatalf("BuildNative failed: %v", err)
+	}
+	lockRaw, err := os.ReadFile(filepath.Join(root, "topdata", "data", "baseitems", "lock.json"))
+	if err != nil {
+		t.Fatalf("read baseitems lock: %v", err)
+	}
+	lockText := string(lockRaw)
+	if !strings.Contains(lockText, `"baseitems:spear": 58`) {
+		t.Fatalf("expected spear lock entry, got:\n%s", lockText)
+	}
+	lockData := map[string]int{}
+	if err := json.Unmarshal(lockRaw, &lockData); err != nil {
+		t.Fatalf("parse baseitems lock: %v", err)
+	}
+	shortspearID, ok := lockData["baseitems:shortspear"]
+	if !ok {
+		t.Fatalf("expected relocated shortspear lock entry to survive, got:\n%s", lockText)
+	}
+	if shortspearID == 58 {
+		t.Fatalf("expected relocated shortspear to use a fresh row id, got lock:\n%s", lockText)
+	}
+
+	got, err := os.ReadFile(filepath.Join(result.Output2DADir, "baseitems.2da"))
+	if err != nil {
+		t.Fatalf("read baseitems.2da: %v", err)
+	}
+	text := string(got)
+	if !strings.Contains(text, "58\tspear") || !strings.Contains(text, fmt.Sprintf("%d\tshortspear", shortspearID)) {
+		t.Fatalf("expected split spear rows in output, got:\n%s", text)
+	}
+}
+
 func TestBuildSkillsIgnoresStaleBaseSpanLockDuringInitialLoad(t *testing.T) {
 	root := testProjectRoot(t)
 	mkdirAll(t, filepath.Join(root, "topdata", "data", "skills", "modules"))