Hi there! I'm using Atahualpa in a multisite network so I got a few sites using the same theme...and I'm not using child theme so.. I wonder if there's any problem if maintaining 3.7.9..or if so, what could happen :/
Sorry but I'm not a very experienced user..

Thank you!

I don't see any issues with staying with 3.7.9 at this time.

I'm a little confused on the subject of updates and what information may be lost.

For example, last update, the custom headers disappeared from all my blogs.

I have just added a bit off code in CSS Inserts to remove a border from one of my sides, leaving the other intact.

Will I have to re-enter that every update?

In a theme upgrade all the theme files are overwritten. This includes any images uploaded to the themes images folder and subfolders such as header images, logo, and favicon so you will have to reupload them. There has always been a way to set the path for the logo and favicon to wherever you want with ../ code. With version 3.7.11 you can now use the same ../ code to set a path to the header images as well that is outside the theme folder. You can read about how to do that in this thread.

All of the theme settings such as what is in CSS Inserts are stored in the database so will be preserved.

Many thanks for the reply - I get it now.