add netdb note about P/X bw boundary

i2p2www/pages/site/docs/how/network-database.html

 {% extends "global/layout.html" %}
 {% block title %}{% trans %}The Network Database{% endtrans %}{% endblock %}
-{% block lastupdated %}2024-04{% endblock %}
-{% block accuratefor %}0.9.62{% endblock %}
+{% block lastupdated %}2025-03{% endblock %}
+{% block accuratefor %}0.9.65{% endblock %}
 {% block content %}
 <h2>{% trans %}Overview{% endtrans %}</h2>
 
@@ -56,14 +56,16 @@ to be present:
     <li><b>M</b>: {% trans amount='48 - 64 KBps' %}{{ amount }} shared bandwidth{% endtrans %}</li>
     <li><b>N</b>: {% trans amount='64 - 128 KBps' %}{{ amount }} shared bandwidth{% endtrans %}</li>
     <li><b>O</b>: {% trans amount='128 - 256 KBps' %}{{ amount }} shared bandwidth{% endtrans %}</li>
-    <li><b>P</b>: {% trans amount='256 - 2000 KBps' %}{{ amount }} shared bandwidth{% endtrans %} (as of release 0.9.20)</li>
+    <li><b>P</b>: {% trans amount='256 - 2000 KBps' %}{{ amount }} shared bandwidth{% endtrans %} (as of release 0.9.20, see note below)</li>
     <li><b>R</b>: {% trans %}Reachable{% endtrans %}</li>
     <li><b>U</b>: {% trans %}Unreachable{% endtrans %}</li>
-    <li><b>X</b>: {% trans amount='2000 KBps' %}Over {{ amount }} shared bandwidth{% endtrans %} (as of release 0.9.20)</li>
+    <li><b>X</b>: {% trans amount='2000 KBps' %}Over {{ amount }} shared bandwidth{% endtrans %} (as of release 0.9.20, see note below)</li>
   </ul>
 "Shared bandwidth" == (share %) * min(in bw, out bw)
 <br>
 For compatibility with older routers, a router may publish multiple bandwidth letters, for example "PO".
+<br>
+Note: the boundary between the P and X bandwidth classes may be either 2000 or 2048 KBps, implementor's choice.
   </li>
   <li><b>netId</b> = 2
 ({% trans %}Basic network compatibility - A router will refuse to communicate with a peer having a different netId{% endtrans %})