How to upgrade Gatsby Starter blog without losing content?

I setup a gatsby blog few months ago using the gatsby-starter-blog and it seems many changes have been made by the contributors of the starter, and I would like to update/upgrade the starter.

I’m now wondering how I can efficiently upgrade it (and its dependencies) without losing my content. I see two options:

Copy the content/ folder to a new Gatsby starter project, but I will lose my commit history (I’m using branches for WIP posts), and I have to setup again all the plugins I installed
Manually change the starter core code, which I can do by creating a new blog locally, and copy/paste all the differences I see between the new version and the one I have

Both approaches are not easy, so I’m wondering if there is something simpler I’m missing?

Thanks