Certain calendar events are missing in the calendar object UC_HOLIDAYS.US in a non 0 client, i.e. GOOD_FRIDAY
The calendar event is still shown in client 0:
Release : 12.3
Component : AUTOMATION ENGINE
All UC_HOLIDAY calendars are part of the initial data (db) and are maintained in client 0. Once they're exported to non 0 clients, they have to be maintained manually.
UC_HOLIDAY calendars do not need to be exported to non 0 clients, because all the calendar events can be referenced from client 0. They are available in all clients.
The screenshot below shows that GOOD_FRIDAY can be retrieved from client 0: