diff --git a/lucene/backward-codecs/src/test/org/apache/lucene/index/TestBackwardsCompatibility.java b/lucene/backward-codecs/src/test/org/apache/lucene/index/TestBackwardsCompatibility.java
index 22b0ab6c726..abb189a4126 100644
--- a/lucene/backward-codecs/src/test/org/apache/lucene/index/TestBackwardsCompatibility.java
+++ b/lucene/backward-codecs/src/test/org/apache/lucene/index/TestBackwardsCompatibility.java
@@ -432,7 +432,9 @@ public class TestBackwardsCompatibility extends LuceneTestCase {
       "6.5.1-cfs",
       "6.5.1-nocfs",
       "6.6.0-cfs",
-      "6.6.0-nocfs"
+      "6.6.0-nocfs",
+      "6.6.1-cfs",
+      "6.6.1-nocfs"
   };
 
   // TODO: on 6.0.0 release, gen the single segment indices and add here:
diff --git a/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.6.6.1-cfs.zip b/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.6.6.1-cfs.zip
new file mode 100644
index 00000000000..7a64c2368e6
Binary files /dev/null and b/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.6.6.1-cfs.zip differ
diff --git a/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.6.6.1-nocfs.zip b/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.6.6.1-nocfs.zip
new file mode 100644
index 00000000000..8b624e37b3c
Binary files /dev/null and b/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.6.6.1-nocfs.zip differ