allout-old-style-prefixes is a variable defined in `allout.el'.
Its value is

  • Automatically becomes buffer-local when set.
  • This variable is safe as a file local variable if its value
    satisfies the predicate `booleanp'.

When non-nil, use only old-and-crusty `outline-mode' `*' topic prefixes.

Non-nil restricts the topic creation and modification
functions to asterix-padded prefixes, so they look exactly
like the original Emacs-outline style prefixes.

Whatever the setting of this variable, both old and new style prefixes
are always respected by the topic maneuvering functions.

You can customize this variable.