<?php
 
/**
 * Get date of next crontab's run
 */ 
 
$cron_format = explode(" ", "00 00 00 01 * *"); // <second> <minute> <hour> <day> <month> <week_day>
$date_diff   = explode(" ", "s i H d m w");     // php Date @link http://p...content-available-to-author-only...p.net/manual/en/function.date.php
$format = [];
 
foreach( $date_diff as $key=>$value)
{
   $format[$value] = $cron_format[$key] !== "*" ? date($value, strtotime($cron_format[$key])) : date($value);
}
 
$spf = sprintf("%s-%s-%s %s:%s:%s", date("Y"), $format["m"], $format["d"], $format["H"], $format["i"], $format["s"]);
 
$date = DateTime::createFromFormat("Y-m-d H:i:s", $spf);
 
echo $date->format("Y-m-d H:i:s");

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