org-allow-promoting-top-level-subtree

org-allow-promoting-top-level-subtree is a variable defined in `org.el'.
Its value is

nil

Documentation:
When non-nil, allow promoting a top level subtree.
The leading star of the top level headline will be replaced
by a #.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.1 of Emacs.