diff --git a/xep-0280.xml b/xep-0280.xml
index 3b071561..d86d3035 100644
--- a/xep-0280.xml
+++ b/xep-0280.xml
@@ -318,6 +318,7 @@
   <section2 topic='Mandatory Support' anchor='mandatory-support'>
     <p>A server implementation can choose to advertise full support of all the rules in §6.1 by including the "urn:xmpp:carbons:rules:0" feature in its service discovery information. If that feature is advertised, the rules above must be treated as REQUIRED and not merely as RECOMMENDED.</p>
     <p>Accordingly, if this feature is advertised, a client MAY rely on the server supporting this exact set of rules.</p>
+    <p>While future versions of this specification (or other specifications) might use a different set of delivery rules, they would signify this by advertising a namespace other than "urn:xmpp:carbons:rules:0".</p>
   </section2>
 </section1>