If you want to update the plugin and have created many popups and have a data that you don't want to lose and redo all the work again, just follow the easy steps below:
1. Go to Popup Builder in your Dashboard
2. Find "Settings" under the Popup builder
3. Go to settings and uncheck "Delete popup data" setting
4. Click "Save changes"
5. Then proceed to updating!
Now you can easily delete the previous version before installing the new one, being sure that your popups won't be gone after the update! ;-)