Change to state from which version the upgrade guide is

marc1706 · marc1706 · commit b043dda5069a · 2024-06-02T17:37:54.000+02:00
diff --git a/development/development/upgrade/400.rst b/development/development/upgrade/400.rst
@@ -1,6 +1,6 @@
-=========
-phpBB 4.0
-=========
+================
+phpBB 3.3 to 4.0
+================
 
 phpBB 4.0 is a major release that contains backward compatibility breaks and also introduces some deprecations.
 
