Whose line is it anyway?

Version control for non-programmers
Some notes on version control: explore how this is supported by GitBook
GitBook has Variants. So on this space, we have two variants: one for the CPD audience and one for the biking audience. https://docs.gitbook.com/editing-content/variants for more info on this.
When you create a Variant, a copy or new version of your content is created. Thereafter, each Variant is edited separately; changes on one Variant are not replicated to another Variant.
I also note that you can share links to pages: https://docs.gitbook.com/features/shareable-links -- this may be another way to provide controlled access to our content.
You can link Gitbook to Github and tie into the branch system there so that Variants are linked automatically to their branches.

Roll-back and Tracked Changes

Rats, well I just messed up some changes that I made while editing this very section. I did not Save my new edits and Merged the old with the new. Sigh.
You can roll back (as we just did, accidentally) to a previous draft version. See notes at https://docs.gitbook.com/collaboration/restore-a-draft -- and that help page has an error. It talks about the 'Merged' tab, but neglects to mention that you must click on the Edits view on the left side first.
And if you click on the ellipses in the top right corner of the small [Save] box, you can highlight the changes you have just made.