$this->rules[self::DMY][self::MD] = self::DM;
$this->rules[self::ALL][self::MD] = self::MD;
$this->rules[self::MDY][self::DM] = self::MD;
$this->rules[self::DMY][self::MD] = self::DM;
$this->rules[self::ALL][self::MD] = self::MD;
$this->rules[self::MDY][self::DM] = self::MD;