[NTG-context] Pocket Diary Photo Calendar: how to specify on which day the week begins?

Hi, I am trying to use the Pocket Diary https://ctan.org/pkg/context-pocketdiary module to create a photo calendar as described in the Calendar Examples https://ctan.org/pkg/context-calendar-examples. The examples work fine. By default weeks begin on Monday. Does anyone know how to specify that weeks begin on Sunday? I have searched through all the setvariable assignments, but nothing seems applicable. I have attached an example file so you needn't retrieve all the examples. Any help would be appreciated. -- With kind regards, Michael http://literatesolutions.com