The schedule for server maintenance is quite regular
Every Tuesday night, 23:00 Server Time (11PM Pacific Standard or Daylight Time), 07:00 Greenwich Mean Time (7 AM GMT), 15:00 Beijing time (3 PM).
Updates are much less frequent, and irregular.
Content Updates Edit
Temporary NPCs Edit
If content is being added temporarily, usually Gift Packs and such that are only offered for a limited time, then NPCs may be created to distribute that content and then removed.
- PWI Iceshard Agent . For Halloween 2015, Ice Shards were added to packs. The Iceshard Agent only existed from November 8th until December 1st (although it was announced as lasting until the 2nd of Dec) Arc News