the string in the panel comes from gnome-desktop I believe. The other strings, calendar widget, lockscreen etc are formatted by gnome-shell.
** Package changed: gnome-settings-daemon (Ubuntu) => gnome-desktop3 (Ubuntu) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-settings-daemon in Ubuntu. https://bugs.launchpad.net/bugs/1443723 Title: GNOME clock displays improper date format for US/EN locale Status in gnome-desktop3 package in Ubuntu: New Bug description: I've actually noticed this for some time and decided to file a bug report in hopes of getting this fixed by 16.04 (or sooner). In the standard GNOME desktop (with US/EN locale set) the date in the clock displays day of week, day of month, month before the time rather than day of week, month, day of month - eg; Mon 13 Apr, 8:06 PM rather than Mon Apr 13, 8:06 PM. The proper format is used both in the screen-lock and the Date & Time settings dialog (see screenshot). This also effects the clock applet in gnome-panel as of Vivid, possibly it's now following g-s-d rather than u-s-d? ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: gnome-settings-daemon 3.14.2-3ubuntu1 ProcVersionSignature: Ubuntu 3.19.0-13.13-generic 3.19.3 Uname: Linux 3.19.0-13-generic i686 ApportVersion: 2.17-0ubuntu2 Architecture: i386 CurrentDesktop: GNOME Date: Mon Apr 13 19:57:57 2015 InstallationDate: Installed on 2015-04-01 (13 days ago) InstallationMedia: Ubuntu-GNOME 15.04 "Vivid Vervet" - Beta i386 (20150331) ProcEnviron: TERM=xterm PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: gnome-settings-daemon UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-desktop3/+bug/1443723/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp