The December 2013 DST Cumulative Update for Windows Operating Systems has been published on Microsoft Download Center. It contains the following changes:

  • Mid-Atlantic Time:
    The Mid-Atlantic time zone is deprecated in this update.

  • Morocco Standard Time:
    Morocco extended the 2013 DST End Date from September 29, 2013 to October 27, 2013. Beginning in 2014, the DST period in Morocco will begin at 2:00 A.M. on the last Sunday in March, and it will end at 3:00 A.M. on the last Sunday in October.

  • Libya Standard Time:
    Libya did not end DST in 2013. From 2014, it will stay at UTC+2 with no DST.  

  • Fiji Standard Time:
    Fiji has changed its DST End Date in 2014 from January 26 to January 19.

For more information on these adjustments, refer to this Microsoft Knowledge Base article: http://support.microsoft.com/kb/2904266.