diff --git a/CHANGES.html b/CHANGES.html
index 7c3f8fc55..b9cdd4317 100644
--- a/CHANGES.html
+++ b/CHANGES.html
@@ -67,6 +67,7 @@ us a note on ns-developers mailing list.</p>
 <li><b>SpectrumPhy</b> function <b>GetRxAntenna</b> is renamed to <b>GetAntenna</b>, and its return value is changed to <b>Ptr<Object></b> instead of <b>Ptr<AntennaModel></b> to support also <b>PhasedArrayModel</b> type of antenna.</li>
 <li><b>vScatt</b> attribute moved from ThreeGppSpectrumPropagationLossModel to ThreeGppChannelModel.</li>
 <li><b>ChannelCondition::IsEqual</b> now has LOS and O2I parameters instead of a pointer to ChannelCondition.</li>
+<li>tcp: <b>TcpWestwood::EstimatedBW</b> trace source changed from <b>TracedValueCallback::Double</b> to <b>TracedValueCallback::DataRate</b>.</li>
 </ul>
 <h2>Changes to build system:</h2>
 <ul>
diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index 9a4349b88..4b6361af6 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -39,6 +39,7 @@ requirements (Note: not all ns-3 features are available on all systems):
 - (wifi) #475 - Wi-Fi: Assert when sending OFDMA DL to STAs with different TIDs
 - (wifi) #480 - wifi: 2.4GHz remote station manager issue
 - (wifi) #507 - wifi: Set CS Required field according to 802.11ax specs
+- (tcp) #531 - tcp: TcpWestwood divide-by-zero and floating point issues
 
 Release 3.35
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