Looks good. I'd probably do it the same way. Alternatively, you can implement part of the logic yourself:

while ($date <= $endDate) {
        say $date;
        $date = 'Time::Piece'->strptime(
            join(' ',
                 $date->year + ($date->mon == 12), $date->mon % 12 + 1
+, 1),
            '%Y %m %d');
}
[download]

Update: You can shorten your original solution. There's no need to parse the date again, just add the days.

while ($date <= $endDate) {
        say $date;
        $date += Time::Seconds::ONE_DAY * $date->month_last_day;
}
[download]