<?php
// Everything you enter here will be executed by our servers. Try it!
var_dump((new DateTime('1970-02-01T18:00:00Z', new DateTimeZone('Europe/Moscow')))->setTimezone(new DateTimeZone('UTC'))->format('Y-m-d\\TH:i:s\\Z'));
var_dump((new DateTime('1970-02-01T18:00:00Z'))->setTimezone(new DateTimeZone('UTC'))->format('Y-m-d\\TH:i:s\\Z'));