GNOME Bugzilla – Bug 320156
Clock shouldn't offer 12 hour clock if strftime("%p") == ""
Last modified: 2015-03-24 13:00:56 UTC
In the en_GB locale, strftime("%p") returns "" this means that if the clock is set to display 12 hour time, it will return useless times like "07:00" to mean 7am and 7pm. Instead, 12 hour time should not be in the drop-down list, and if it is set to that, in gconf, it should display 24 hour time anyway.
Good point.
Fixed in HEAD.