- date_default_timezone_set: documentation ( source)
<?php
date_default_timezone_set('Africa/Addis_Ababa');
echo DateTime::createFromFormat('Y-m-d H:i:s', '1908-04-30 23:59:59')->format(DATE_ATOM) . PHP_EOL;
echo DateTime::createFromFormat('Y-m-d H:i:s', '1908-05-01 00:00:00')->format(DATE_ATOM) . PHP_EOL;