UserModel::getAllSubordinates

public function getAllSubordinates(): array
{
	if ($this->allSubordinates === null)
	{
		$this->allSubordinates = [];
		if ($this->userId === 0)
		{
			return $this->allSubordinates;
		}

		$this->allSubordinates = BitrixTasksIntegrationIntranetUser::getSubordinate($this->userId, null, true, true);
	}
	return $this->allSubordinates;
}