diff --git a/support/Release notes.txt b/support/Release notes.txt
index 49b9aa80..f8f3795e 100644
--- a/support/Release notes.txt	
+++ b/support/Release notes.txt	
@@ -1,6 +1,7 @@
 ===============================================================================
 20.33.0
 Added etl::message_broker to message framework
+Added 'successor' parameter constructors to all etl::imessage_router derived classes
 Added etl::binary_search to algorithm.h
 Standardise conditional compilation macros for ETL_USING_CPP11 and ETL_USING_STL