diff --git a/USER_MANUAL.html b/USER_MANUAL.html
index 6a2dcef4e..658611eab 100644
--- a/USER_MANUAL.html
+++ b/USER_MANUAL.html
@@ -643,7 +643,7 @@ <h1 data-number="17" id="glossary"><span class="header-section-number">17</span>
 </tbody>
 </table>
 <h1 data-number="18" id="release-notes"><span class="header-section-number">18</span> Release Notes</h1>
-<h2 data-number="18.1" id="v1.9.9-tbd-2024"><span class="header-section-number">18.1</span> V1.9.9 TBD 2024</h2>
+<h2 data-number="18.1" id="v1.9.9-april-2024"><span class="header-section-number">18.1</span> V1.9.9 April 2024</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -664,6 +664,10 @@ <h2 data-number="18.1" id="v1.9.9-tbd-2024"><span class="header-section-number">
 <ul>
 <li>Remove broken links in README. (PR #709)</li>
 </ul></li>
+<li>Build system:
+<ul>
+<li>Add ability to build without LPCNet in preparation for potential future deprecation of 2020/2020B. (PR #711)</li>
+</ul></li>
 </ol>
 <h2 data-number="18.2" id="v1.9.8-february-2024"><span class="header-section-number">18.2</span> V1.9.8 February 2024</h2>
 <ol type="1">
diff --git a/USER_MANUAL.pdf b/USER_MANUAL.pdf
index e60ba1c55..5cf6a29ca 100644
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