<?php
$current_date = date('d-M-Y g:i:s A');
echo $current_date."\n";
$current_time = strtotime($current_date);
$frac = 900;
$r = $current_time % $frac;
$new_time = $current_time + ($frac-$r);
$new_date = date('d-M-Y g:i:s A', $new_time);
echo $new_date."\n";