diff --git a/navsea_tile_builder.py b/navsea_tile_builder.py
index 7a5bb2e..648cdab 100644
--- a/navsea_tile_builder.py
+++ b/navsea_tile_builder.py
@@ -1380,11 +1380,19 @@ def parse_args() -> argparse.Namespace:
     parser.add_argument(
         "--strip-legacy-japanese-delivery",
         action="store_true",
+        dest="strip_legacy_japanese_delivery",
         help="drop mapped Japanese structural keys from delivery tiles after writing standardized aliases",
     )
+    parser.add_argument(
+        "--keep-legacy-japanese-delivery",
+        action="store_false",
+        dest="strip_legacy_japanese_delivery",
+        help="keep mapped Japanese structural keys in delivery tiles for legacy compatibility",
+    )
     parser.add_argument("--fid-key")
     parser.add_argument("--fid-key-id", default="navsea-fid-key-v1")
     parser.add_argument("--bundle-id", default="navsea-reversible-v1")
+    parser.set_defaults(strip_legacy_japanese_delivery=True)
     args = parser.parse_args()
 
     if not args.all_tiles: