Did you change the "Holiday Calendar of Personnel Sub Area in Nove 2013" or did you create a new one?
If you modified the Holiday Calendar, did you re-generate all PWS associated with it, as of the month of the Holiday change?
When you created PWS Rule GR1N, did you generate it from December 2013 up to December 2014 (or more)?
When I look at the screen capture of your employee's monthly work schedule, I notice that the PWS and WSRule are both GR1N while all Daily Work Schedules are GNR1. Is that what it should be?