<?php
 
// Considerando que o timezone do servidor esteja configurado:
date_default_timezone_set('America/Sao_Paulo');
 
$date = "01-05-2017 08:00:00";
 
// Data devidamente convertida de UTC para UTC-3:
$date1 = new DateTime($date, new DateTimeZone("UTC"));
$date1->setTimeZone(new DateTimeZone("America/Sao_Paulo"));
 
echo $date1->format('Y-m-d H:i:s'), PHP_EOL;
 
// Data utilizando o timezone atual do servidor:
$date2 = new DateTime($date);
$date2->setTimeZone(new DateTimeZone("America/Sao_Paulo"));
 
echo $date2->format('Y-m-d H:i:s'), PHP_EOL;

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