diff --git a/ArduSub/ReleaseNotes.txt b/ArduSub/ReleaseNotes.txt
index 0a6b1c75e5..937999ce18 100644
--- a/ArduSub/ReleaseNotes.txt
+++ b/ArduSub/ReleaseNotes.txt
@@ -1,5 +1,12 @@
 APM:Sub Release Notes:
 
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Sub 4.0.3 5-March-2021
+
+ - No longer report battery percentage
+ - Do not override RNGFND1_TYPE
+ - Relax position controller when entering Depth Hold mode
+
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Sub 4.0.2 21-September-2020