PrototypeItem::onBeforeUpdate

static function onBeforeUpdate(Event $event): ORMEventResult
{
	/** @var Item $item */
	$item = $event->getParameter('object');
	if($item->isChanged('STAGE_ID'))
	{
		$item->setPreviousStageId($item->remindActual('STAGE_ID'));
	}
	return parent::onBeforeUpdate($event);
}