add_filter( 'frm_pdfs_email_attachment_args', function( $pdf_args, $args ) {
	if ( 1 != $args['form']->id || ! empty( $pdf_args['view'] ) ) { // Replace 1 with your form ID.
		return $pdf_args;
	}

	$pdf_args['view'] = 70; // Replace 70 with your first attachment view ID.
	$pdf_args['id']   = $args['entry']->id;

	return $pdf_args;
}, 10, 2 );

add_filter( 'frm_notification_attachment', function( $attachments, $form, $args ) {
	if ( 1 != $form->id ) { // Replace 1 with your form ID.
		return $attachments;
	}

	// Attach a second PDF.
	$pdf_args = array(
		'mode'     => FrmPdfsAppController::FILE_MODE,
		'view'     => 139, // Replace 139 with your second attachment view ID.
		'id'       => $args['entry']->id,
		'filename' => '{form_name}-{date format="Y-m-d"}-{key}-2',
	);

	$args['form'] = $form;

	$file_path = FrmPdfsAppController::generate_entry_pdf( $args['entry'], $pdf_args );
	if ( $file_path ) {
		$attachments[] = $file_path;

		add_action(
			'frm_notification',
			function() use ( $file_path ) {
				FrmPdfsAppController::delete_file( $file_path );
			}
		);
	}

	return $attachments;
}, 10, 3 );