Service/Account/Balance/Calc/A/ProcessOneAccount.php
private function getBalancesLastDate($accId)
    {
        $reqLastDate = new ALastDateRequest();
        $reqLastDate->setAccountId($accId);
        $respLastDate = $this->servBalanceLastDate->exec($reqLastDate);
        $result = $respLastDate->getLastDate();
        return $result;
    }
private function getBalancesLastDate($accId)
    {
        $reqLastDate = new ALastDateRequest();
        $reqLastDate->setAccountId($accId);
        $respLastDate = $this->servBalanceLastDate->exec($reqLastDate);
        $result = $respLastDate->getLastDate();
        return $result;
    }
Get the last datestamp for existing balances for given asset.

@param int $accId
@return string
@throws \Exception