update release notes
diff --git a/release-notes/VERSION b/release-notes/VERSION
index 64f4432..eccef04 100644
--- a/release-notes/VERSION
+++ b/release-notes/VERSION
@@ -8,6 +8,9 @@
 
 #219: SqlDateSerializer does not obey SerializationConfig.Feature.WRITE_DATES_AS_TIMESTAMPS
  (reported by BrentDouglas@github)
+#291: @JsonTypeInfo with As.EXTERNAL_PROPERTY doesn't work if external type property
+  is referenced more than once
+ (reported by Starkom@github)
 #476: Allow "Serialize as POJO" using `@JsonFormat(shape=Shape.OBJECT)` class annotation
 #507: Support for default `@JsonView` for a class
  (suggested by Mark W)