diff --git a/zip-0221.html b/zip-0221.html
index 14532a69..24043fe7 100644
--- a/zip-0221.html
+++ b/zip-0221.html
@@ -212,7 +212,7 @@ License: MIT</pre>
                             <dt>Internal or root node</dt>
                             <dd>Inherited from the left child.</dd>
                         </dl>
-                        <p>Serialized as <code>nTime</code> (<code>uint32</code>).</p>
+                        <p>Serialized as <code>nTime</code> (<code>uint32</code>). This will overflow on 2106-02-07.</p>
                     </li>
                     <li><code>nLatestTimestamp</code>
                         <dl>
@@ -222,7 +222,7 @@ License: MIT</pre>
                             <dd>Inherited from the right child.</dd>
                         </dl>
                         <p>Note that due to timestamp consensus rules, <code>nLatestTimestamp</code> may be smaller than <code>nEarliestTimestamp</code> in some subtrees. This may occur within subtrees smaller than <code>PoWMedianBlockSpan</code> blocks.</p>
-                        <p>Serialized as <code>nTime</code> (<code>uint32</code>).</p>
+                        <p>Serialized as <code>nTime</code> (<code>uint32</code>). This will overflow on 2106-02-07.</p>
                     </li>
                     <li><code>nEarliestTargetBits</code>
                         <dl>
diff --git a/zip-0221.rst b/zip-0221.rst
index 162791d6..5587dfc9 100644
--- a/zip-0221.rst
+++ b/zip-0221.rst
@@ -214,7 +214,7 @@ Each MMR node is defined as follows:
    Internal or root node
      Inherited from the left child.
 
-   Serialized as ``nTime`` (``uint32``).
+   Serialized as ``nTime`` (``uint32``). This will overflow on 2106-02-07.
 
 3. ``nLatestTimestamp``
 
@@ -228,7 +228,7 @@ Each MMR node is defined as follows:
    ``nEarliestTimestamp`` in some subtrees. This may occur within subtrees smaller than
    ``PoWMedianBlockSpan`` blocks.
 
-   Serialized as ``nTime`` (``uint32``).
+   Serialized as ``nTime`` (``uint32``). This will overflow on 2106-02-07.
 
 4. ``nEarliestTargetBits``