org-list-allow-alphabetical

org-list-allow-alphabetical is a variable defined in `org-list.el'.
Its value is

nil

Documentation:
Non-nil means single character alphabetical bullets are allowed.

Both uppercase and lowercase are handled. Lists with more than
26 items will fallback to standard numbering. Alphabetical
counters like "[@c]" will be recognized.

This variable needs to be set before org.el is loaded. If you
need to make a change while Emacs is running, use the customize
interface or run the following code after updating it:

(when (featurep 'org-element) (load "org-element" t t))

You can customize this variable.

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