diff --git a/2025/challenge.html b/2025/challenge.html
index d2d9758147..abf709c023 100644
--- a/2025/challenge.html
+++ b/2025/challenge.html
@@ -479,7 +479,7 @@ <h2 id="fun-challenge-for-2025ayu">Fun challenge for <a href="ayu/index.html">20
 <div id="ayu_solution">
 <h3 id="fun-challenge-solution-for-2025ayu">Fun challenge solution for <a href="ayu/index.html">2025/ayu</a></h3>
 </div>
-<p><a href="https://github.com/Master-Hash">Master-Hash</a> on <strong>2026 Jun 09</strong> presented this
+<p>GitHub user <a href="https://github.com/Master-Hash">Master-Hash</a> on <strong>2026 Jun 09</strong> presented this
 <a href="https://github.com/Master-Hash/ioccc--ayu-2025-fun-challenge">2025/ayu fun challenge solution</a>.</p>
 <div id="cable">
 <h2 id="fun-challenges-for-2025cable">Fun challenges for <a href="cable/index.html">2025/cable</a></h2>
@@ -604,11 +604,14 @@ <h2 id="fun-challenge-for-2025endoh2">Fun challenge for <a href="endoh2/index.ht
 <div id="endoh2_solution">
 <h3 id="fun-challenge-solution-for-2025endoh2">Fun challenge solution for <a href="endoh2/index.html">2025/endoh2</a></h3>
 </div>
-<p>As <a href="https://github.com/antoine-mathys">antoine-mathys</a> pointed out on <strong>2026 July 11</strong>,
-that <a href="endoh2/prog.alt.c">2025/endoh2/prog.alt.c</a> solved this fun challenge.</p>
-<p>Apologies: before we wrote this fun challenge page, <a href="https://github.com/uguu-org">omoikane</a> on
-<strong>2026 Jun 7</strong> contributed the solution that we added as <a href="endoh2/prog.alt.c">2025/endoh2/prog.alt.c</a>.
-We forgot this happened when we created this fun challenge page.</p>
+<p>GitHub user <a href="https://github.com/uguu-org">omoikane</a> on
+<strong>2026 Jun 7</strong> contributed a solution that was added as
+<a href="endoh2/prog.alt.c">2025/endoh2/prog.alt.c</a>.</p>
+<p><strong>NOTE</strong>: The above mentioned file was added before this page was available.
+Future solutions to other fun challenges should be presented as external GitHub repos.</p>
+<p>See the
+FAQ on “<a href="../faq.html#solve_fun_challenge">submitting a solution</a>”
+for more details.</p>
 <div id="endoh3">
 <h2 id="fun-challenge-for-2025endoh3">Fun challenge for <a href="endoh3/index.html">2025/endoh3</a></h2>
 </div>
diff --git a/2025/challenge.md b/2025/challenge.md
index 6b28ab90e4..aac19cf13e 100644
--- a/2025/challenge.md
+++ b/2025/challenge.md
@@ -36,7 +36,7 @@ and up to some reasonable limit.
 ### Fun challenge solution for [2025/ayu](ayu/index.html)
 </div>
 
-[Master-Hash](https://github.com/Master-Hash) on **2026 Jun 09** presented this
+GitHub user [Master-Hash](https://github.com/Master-Hash) on **2026 Jun 09** presented this
 [2025/ayu fun challenge solution](https://github.com/Master-Hash/ioccc--ayu-2025-fun-challenge).
 
 
@@ -253,12 +253,16 @@ Choose a colors/brightness palette to represent the charge intensity.
 ### Fun challenge solution for [2025/endoh2](endoh2/index.html)
 </div>
 
-As [antoine-mathys](https://github.com/antoine-mathys) pointed out on **2026 July 11**,
-that [2025/endoh2/prog.alt.c](endoh2/prog.alt.c) solved this fun challenge.
+GitHub user [omoikane](https://github.com/uguu-org) on
+**2026 Jun 7** contributed a solution that was added as
+[2025/endoh2/prog.alt.c](endoh2/prog.alt.c).
 
-Apologies: before we wrote this fun challenge page, [omoikane](https://github.com/uguu-org) on
-**2026 Jun 7** contributed the solution that we added as [2025/endoh2/prog.alt.c](endoh2/prog.alt.c).
-We forgot this happened when we created this fun challenge page.
+**NOTE**: The above mentioned file was added before this page was available.
+Future solutions to other fun challenges should be presented as external GitHub repos.
+
+See the
+FAQ on "[submitting a solution](../faq.html#solve_fun_challenge)"
+for more details.
 
 
 <div id="endoh3">
diff --git a/sitemap.xml b/sitemap.xml
index 3cf67ea0f4..69b5468575 100644
--- a/sitemap.xml
+++ b/sitemap.xml
@@ -15994,11 +15994,11 @@
 </url>
 <url>
     <loc>https://www.ioccc.org/2025/challenge.html</loc>
-    <lastmod>2026-07-12T03:10:45+00:00</lastmod>
+    <lastmod>2026-07-13T00:07:42+00:00</lastmod>
 </url>
 <url>
     <loc>https://www.ioccc.org/2025/challenge.md</loc>
-    <lastmod>2026-07-12T03:09:26+00:00</lastmod>
+    <lastmod>2026-07-13T00:07:31+00:00</lastmod>
 </url>
 <url>
     <loc>https://www.ioccc.org/2025/diels-grabsch/2025_diels-grabsch.tar.bz2</loc>