Oh man, you crushed that last Series! Your group was engaged, and everything went smoothly. Well no need to start from scratch, you can duplicate that Series and use it as a template!
To do so is simple:
Find the Series in Coleader.
Tap the menu (the three dots near the Series Title)
Tap "Duplicate this Series"
Select the Group where you'd like the duplicate to go, then tap "Duplicate Series"
Once copied, you can go into the duplicated Series and delete or add Sessions as your new Series requires. To delete sessions, click on the three dots in the Session block and select "Delete Session."
You've now got a copy of that Series in your Group, ready to be adapted for whatever you need!