ChangeAgent on "[Plugin: Wordfence Security] changes to updraftplus.php reported by Wordfence"

I use Wordfence. It gave me the following message:

Filename: wp-content/plugins/updraftplus/updraftplus.php
File type: Plugin
Issue first detected: 12 mins ago.
Severity: Warning
Status New

This file belongs to plugin "UpdraftPlus - Backup/Restore" version "1.8.8" and has been modified from the file that is distributed by WordPress.org for this version. Please use the link to see how the file has changed. If you have modified this file yourself, you can safely ignore this warning. If you see a lot of changed files in a plugin that have been made by the author, then try uninstalling and reinstalling the plugin to force an upgrade. Doing this is a workaround for plugin authors who don't manage their code correctly. [See our FAQ on http://www.wordfence.com for more info]

Is this a problem? Why does this happen? Do I need to be worried?

http://wordpress.org/plugins/wordfence/