If you want to duplicate your timeline and keep your settings, you can do so by simply pressing the three dots to the right of the timeline and then click duplicate.
The new duplicated timeline can be kept for future reference and made inactive.
Now, you can simply make any changes you like to the original timeline and it will remain connected to your pages and other integrations.
Please note: when you duplicate your new timeline, a new 'wtl' is created, therefore if you wish to use the newly duplicated timeline, you must update the settings and insert the new registration, etc codes to your pages.