diff --git a/P5/Source/Specs/classRef.xml b/P5/Source/Specs/classRef.xml
index 3f8e68792d..b9b938649d 100644
--- a/P5/Source/Specs/classRef.xml
+++ b/P5/Source/Specs/classRef.xml
@@ -18,7 +18,12 @@
       <desc versionDate="2024-02-28" xml:lang="ja">指示されたソースの中の要求されたクラスに対して使用される識別子。</desc>
       <datatype><dataRef key="teidata.xmlName"/></datatype>
     </attDef>
-    <attDef ident="expand" usage="opt">
+    <attDef ident="expand" usage="opt" validUntil="2024-10-13">
+      <desc type="deprecationInfo" versionDate="2024-04-13" xml:lang="en">
+        Since classes are meant to be an unordered data structure, the <att>expand</att> attribute will no longer be supported.
+        Class members will be considered to be in alternation. To impose a sequence it will be necessary use <gi>elementRef</gi> with 
+        references to the individual elements.
+      </desc>
       <desc versionDate="2013-11-21" xml:lang="en">indicates how references
       to this class within a content model should be interpreted.</desc>
       <desc versionDate="2024-02-28" xml:lang="ja">内容モデル内でこのクラスへの参照がどのように解釈されるべきなのかを示す。</desc>
diff --git a/P5/Source/Specs/classSpec.xml b/P5/Source/Specs/classSpec.xml
index a9a1c619ee..f38e05b493 100644
--- a/P5/Source/Specs/classSpec.xml
+++ b/P5/Source/Specs/classSpec.xml
@@ -88,7 +88,11 @@ that is a group of
         </valItem>
       </valList>
     </attDef>
-    <attDef ident="generate" usage="opt">
+    <attDef ident="generate" usage="opt" validUntil="2024-10-13">
+      <desc type="deprecationInfo" versionDate="2024-04-13" xml:lang="en">
+        Since classes are meant to be an unordered data structure, the <att>generate</att> attribute will no longer be supported. 
+        Some content model operations may be handled at instantiation with <gi>classRef</gi>, with the exclusion of imposing a sequence.
+      </desc>
       <desc versionDate="2007-10-23" xml:lang="en">indicates which alternation and sequence instantiations
 	of a model class may be referenced. By default, all variations
 	are permitted.</desc>