diff --git a/CST100Starliner/CST100Starliner-v2.1.ckan b/CST100Starliner/CST100Starliner-v2.1.ckan
index ca9f95083b..fdbd383bd0 100644
--- a/CST100Starliner/CST100Starliner-v2.1.ckan
+++ b/CST100Starliner/CST100Starliner-v2.1.ckan
@@ -1,5 +1,5 @@
 {
-    "spec_version": "v1.18",
+    "spec_version": "v1.16",
     "comment": "Version file has a syntax error",
     "identifier": "CST100Starliner",
     "name": "CST-100 Starliner",