Use MD_STD::strtotime() over strtotime()

src/MD_STD.php

@@ -944,7 +944,7 @@ public static function date_to_int(string $date):int {
             return -1 * intval(str_replace("-", "", ltrim($date, "0-")));
         }
 
-        return intval(date("Ymd", strtotime($date)));
+        return intval(date("Ymd", self::strtotime($date)));
 
     }