I’ve noticed that I have to select the new date value twice before the ‘change’ event is triggered
The date time picker is inside a template that is used for table cell editing

<ng-template #scheduledDateTemplate let-row="row" let-rowIndex="rowIndex" let-value="value">
          <span
            (click)="startInlineEdit(rowIndex + '-scheduled', rowIndex)"
            *ngIf="!isInlineEditing(rowIndex + '-scheduled')"
            title="Click to edit"
          >
            {{ value }}
          </span>
  <smart-date-time-picker
    *ngIf="isInlineEditing(rowIndex + '-scheduled')"
    formatString="ddd dd-MMM-yyyy"
    dropDownDisplayMode="calendar"
    drop-down-position="bottom"
    calendar-button placeholder="for"
    style="width: 180px"
    [nullable]="true"
    [autoClose]="true"
    [value]="value"
    [dropDownAppendTo]="'body'"
    (change)="updateScheduledValue($event)"
  >
  </smart-date-time-picker>
</ng-template>