diff --git a/types/office-js-preview/index.d.ts b/types/office-js-preview/index.d.ts
index 20155654e40705..2d51cb9788c7c2 100644
--- a/types/office-js-preview/index.d.ts
+++ b/types/office-js-preview/index.d.ts
@@ -72134,7 +72134,7 @@ declare namespace Excel {
          *
          * @param dateText Is text that represents a date in a Microsoft Excel date format, between 1/1/1900 or 1/1/1904 (depending on the workbook's date system) and 12/31/9999.
          */
-        datevalue(dateText: string | number | Excel.Range | Excel.RangeReference | Excel.FunctionResult<any>): FunctionResult<number>;
+        datevalue(dateText: string | Excel.Range | Excel.RangeReference | Excel.FunctionResult<any>): FunctionResult<number>;
         /**
          * Returns the day of the month, a number from 1 to 31.
          *
@@ -148585,8 +148585,7 @@ declare namespace Word {
          * Adds a new `ListTemplate` object. Note: This operation isn't allowed if the collection represents list templates from a {@link Word.ListTemplateGallery}.
          *
          * @remarks
-         * [Api set: WordApi BETA (PREVIEW ONLY)]
-         * @beta
+         * [Api set: WordApiDesktop 1.5]
          *
          * @param options Optional. Options for adding a new list template.
          */
@@ -148637,24 +148636,21 @@ declare namespace Word {
      * Represents the options for the {@link Word.ListTemplateCollection | ListTemplateCollection.add} method.
      *
      * @remarks
-     * [Api set: WordApi BETA (PREVIEW ONLY)]
-     * @beta
+     * [Api set: WordApiDesktop 1.5]
      */
     interface ListTemplateAddOptions {
         /**
          * If provided, specifies the name of the list template to be added.
          *
          * @remarks
-         * [Api set: WordApi BETA (PREVIEW ONLY)]
-         * @beta
+         * [Api set: WordApiDesktop 1.5]
          */
         name?: string;
         /**
          * If provided, specifies whether to apply outline numbering to the new list template. The default value is `false`.
          *
          * @remarks
-         * [Api set: WordApi BETA (PREVIEW ONLY)]
-         * @beta
+         * [Api set: WordApiDesktop 1.5]
          */
         outlineNumbered?: boolean;
     }
diff --git a/types/office-js/index.d.ts b/types/office-js/index.d.ts
index 1ce8d7b71c557c..a8ee98c14c0f86 100644
--- a/types/office-js/index.d.ts
+++ b/types/office-js/index.d.ts
@@ -66853,7 +66853,7 @@ declare namespace Excel {
          *
          * @param dateText Is text that represents a date in a Microsoft Excel date format, between 1/1/1900 or 1/1/1904 (depending on the workbook's date system) and 12/31/9999.
          */
-        datevalue(dateText: string | number | Excel.Range | Excel.RangeReference | Excel.FunctionResult<any>): FunctionResult<number>;
+        datevalue(dateText: string | Excel.Range | Excel.RangeReference | Excel.FunctionResult<any>): FunctionResult<number>;
         /**
          * Returns the day of the month, a number from 1 to 31.
          *
@@ -139699,6 +139699,15 @@ declare namespace Word {
         context: RequestContext;
         /** Gets the loaded child items in this collection. */
         readonly items: Word.ListTemplate[];
+        /**
+         * Adds a new `ListTemplate` object. Note: This operation isn't allowed if the collection represents list templates from a {@link Word.ListTemplateGallery}.
+         *
+         * @remarks
+         * [Api set: WordApiDesktop 1.5]
+         *
+         * @param options Optional. Options for adding a new list template.
+         */
+        add(options?: Word.ListTemplateAddOptions): Word.ListTemplate;
         /**
          * Queues up a command to load the specified properties of the object. You must call `context.sync()` before reading the properties.
          *
@@ -139731,6 +139740,28 @@ declare namespace Word {
         */
         toJSON(): Word.Interfaces.ListTemplateCollectionData;
     }
+    /**
+     * Represents the options for the {@link Word.ListTemplateCollection | ListTemplateCollection.add} method.
+     *
+     * @remarks
+     * [Api set: WordApiDesktop 1.5]
+     */
+    interface ListTemplateAddOptions {
+        /**
+         * If provided, specifies the name of the list template to be added.
+         *
+         * @remarks
+         * [Api set: WordApiDesktop 1.5]
+         */
+        name?: string;
+        /**
+         * If provided, specifies whether to apply outline numbering to the new list template. The default value is `false`.
+         *
+         * @remarks
+         * [Api set: WordApiDesktop 1.5]
+         */
+        outlineNumbered?: boolean;
+    }
     /**
      * Represents a gallery of list templates of the same {@link Word.ListTemplateGalleryType}.
      *