<?php
$inicio = new DateTime('2019-11-12');
$fim = clone $inicio;
$fim->modify('-1 month'); // 1 mês antes
$diff = $fim->diff($inicio);
// intervalo de "menos 1 dia"
$intervalo = DateInterval::createFromDateString('-1 day');
$periodo = new DatePeriod($inicio, $intervalo, $diff->days - 1);
foreach ($periodo as $p) {
echo $p->format("Y-m-d") . PHP_EOL;
}
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