The timeline on every page is edited using the same method by following these steps.
1. Check which group is being used on the page where you want to change the timeline. click Edit site.
2. Check the group in the shortcode. And take note of it.
3. click left menu > Timeline > All Time line.
4. Fine Timeline Groups : Group 2
5. click edit
6. How to change see image below. for add using detail to enter same.
7. click save to finish changed.