diff --git a/addons/stock_calendar/stock_calendar_view.xml b/addons/stock_calendar/stock_calendar_view.xml
index 1c321b4ad78..86d3dcd5e29 100644
--- a/addons/stock_calendar/stock_calendar_view.xml
+++ b/addons/stock_calendar/stock_calendar_view.xml
@@ -30,9 +30,9 @@
             <field name="model">procurement.order</field>
             <field name="inherit_id" ref="procurement.procurement_form_view"/>
             <field name="arch" type="xml">
-                <xpath expr="//div[@name='button_box']" position="inside">
+                <field name="state" position="before">
                     <button name="assign_group_date" string="Calculate dates according to Orderpoint" type="object"/>
-                </xpath>
+                </field>
             </field>
         </record>