         let direction: UIPageViewControllerNavigationDirection = isLaterMonth ? .forward : .reverse
         
         self._displayedMonthAndYear = roundedDate
-        self._firstDisplayedDay = roundedDate.startOf(component: .weekOfYear)
+        self._firstDisplayedDay = self._getFirstDisplayedDay()
         self._switchTo(daysVC: vc, direction: direction, animated: animated)
+    }
+}
+
+
+// MARK: Helpers
+private extension CalendarVC {
+    func _getFirstDisplayedDay() -> Date {
+        return self._displayedMonthAndYear.startOf(component: .weekOfMonth)
     }
 }
 

        self.embed(pageVC, into: self._calendarVCView.pageVCViewContainer)
        pageVC.view.autoresizingMask = [.flexibleWidth, .flexibleHeight]
    }
}



            navigationOrientation: .horizontal,
            options: nil
        )
        
        pageVC.delegate = self
        pageVC.dataSource = self
