(a)unless the reporting financial institution elects otherwise, either with respect to all pre-existing entity accounts or, separately, with respect to any clearly identified group of such accounts, a pre-existing entity account with an aggregate account balance or value which does not exceed an amount equivalent to two hundred and fifty thousand U.S. dollars as on the 30th June, 2014 (in case of a U.S. reportable account), or as the case may be, 31st December, 2015 (in case of other reportable account), is not required to be reviewed, identified, or reported as a reportable account until the aggregate account balance or value exceeds an amount equivalent to two hundred and fifty thousand U.S. dollars as of the last day of any subsequent calendar year;