From OpenStreetMap Wiki
This template includes all the material for the Community Update heders.
All dates are computed from the subname page.
Example with passed date 2009-01-01 :
Community Update from 10 January 2011 to 16 January 2011 (week 2011-02)
Image Of the Week 2011-02
no previous page - no page CU header/2011-01-17 create it