function onBeforeWrite() {

		if (!self::$has_written && $this->isChanged('Date', 2) && $this->isChanged('SendEmail', 2)) {

			$NewsletterFile = DataObject::get_by_id("File", $this->NewsletterAttachmentID);
			$NewsletterGroup = DataObject::get_by_id("Group", '5');


			$data['URL'] = $NewsletterFile->Filename;
			$data['Date'] = date('d/m/Y', strtotime($this->Date));

			$this->EmailsNotSent()->addMany($NewsletterGroup->Members());

			foreach ($NewsletterGroup->Members() as $member) {

				$From = 'test@test.com';
				$To = $member->Email;
				$Subject = "Test Newsletter ".$data['Date'];
				$email = new Email($From, $To, $Subject);

				$attachedfile = $NewsletterFile->Filename;
				$email->attachFile($attachedfile, 'Newsletter-'.$this->Date.'.pdf');

				$email->setTemplate('WeeklyNewsletterEmail');

				$email->populateTemplate($data);

				$email->send();

				$this->EmailsNotSent()-> remove($member);
				usleep(2000);
				self::$has_written = true;

			}}

		parent::onBeforeWrite();
	}