iOS and Objective-C: Repeating an event every quarter
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I need to have an event repeat every "quarter" (which I assume means moving up 3 months approximately). So I could expect this to move the date (but it doesn't):

        NSDateComponents *component = [[NSDateComponents alloc] init]; // quarter
        component.quarter = 1;
    
        self.todoStartDate = [[NSCalendar currentCalendar] dateByAddingComponents: component toDate:self.todoStartDate options: 0];


Is there anything wrong with adding a "quarter" to a date? It works fine when adding a day or a week, but not with a "quarter".