The current date selector on Special:CentralNotice is hand-crafted and this has several problems:
- It may require separate maintenance.
- It assumes the USA order of month, day, year.
- With an RTL interface language the order becomes even stranger: year, day, month.
It should be replaced by the jQuery datepicker, which is already used in at least two extension, is well maintained by its own and has pretty good internationalization.