@Input() budgetDates: BudgetDate[] = [];

this.budgetService.getBudgetDays(startDate, finishDate).subscribe({
      next(budgetDates: BudgetDate[]) {
        self.timelineBudgetDates = self.processDates(budgetDates);
        self.changeDetectorRef.detectChanges();
      }
    });

<app-timeline [budgetDates]="timelineBudgetDates"></app-timeline>