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<?php $date = new \DateTime('+21 days'); $date->modify('wednesday'); var_dump($date);
based on 7Yh2r
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.26, 7.4.0 - 7.4.14, 8.0.0 - 8.0.2
object(DateTime)#1 (3) { ["date"]=> string(26) "2018-07-25 00:00:00.000000" ["timezone_type"]=> int(3) ["timezone"]=> string(16) "Europe/Amsterdam" }