How do I check day for cross month

I have an activity that only perform in a date range regardless month/year. I need to validate if the current date is >= 30 and <= 05 (next month).

Sample code below:

$t = microtime(true);
$micro = sprintf("%06d",($t - floor($t)) * 1000000);
$d = new DateTime( date('Y-m-d H:i:s.'.$micro, $t) );
$date = substr($d->format("d"),0,2);

if($date >= 30000000 && $date <= 05000000){
    $validate = true;
}

I simply cannot use >= 30 and <= 05 as it is an invalid range. Or should I need to code:

if($date = 30 || $date = 31 || $date = 01 || $date = 02 || $date = 03 || $date = 04 || $date = 05){
    $validate = true;
}