The first and foremost thing to do is backup your wordpress website, no matter what. Before making any changes you should backup your website.
Manually updating WordPress plugins and themes is easier than you think. It can be done using file manager in control panel, via ftp or using this WordPress plugin. Following links will be helpful to you:
How many websites can I install these WordPress premium plugins or themes?
UNLIMITED, yes you read that right, you can install these themes or plugins on unlimited websites. That is one of the benefit of GPL, it allows you to install the software on any no. of sites.
Usually developers offer their support for x amount of websites such as 1, 3 , 5 or 25 websites etc. They are offering their tech support and automatic updates for x no. of websites. (Note: we neither provide support not automatic updates, if you need them you should buy directly from developers.)
How can you offer premium WordPress products at low prices?
All the products that you see here are under GPL license. Thus we can distribute the same files to our GPL Guru Club members. Our club members save when they don’t need tech support or automatic updates.
Everything listed on our website whether it is wordpress plugins, themes or extensions, all are 100% open source GPL licensed software. We provide you same files we receive from developers. High price at developer sites includes their direct support and automatic updates with files. We just provide the files only.
WordPress.org itself is an open source software and under the GPL license.
The GPL licensed software allows anyone to freely use, share, modify and redistribute software as they please.
WordPress plugin, extension, and theme Developers who create derivative works (their files need WordPress software to function) are encouraged to adopt the same licensing structure as WordPress, and most do. This enables us to redistribute the software. Our club membership includes the work by premium developers such as: Elegant Themes, WooThemes, Gravity Forms, AppThemes, WPML and others at these lower club membership discount prices.
100% Originals files
All items contained within the directory on GPL Studio are developed by third-party developers and redistributed by GPL Studio under the terms of the General Public Licence (GPL)