When you have created Collections and sent it to your target audience, you need not fret not being able to make changes to it.
Paperflite lets you to edit it unlike conventional emails that are permanent. You can make the below changes to a Collection even after sharing the Collection:
Change the Name of the Collection
Change the text in the Collection
Edit the font of the text in the Collection
Edit the background image
Add/remove content assets from the Collection
Click here to know how to edit Collections.