When creating adding a template to a sequence email, you'll be asked to decide if you'd like to clone or link the template in the sequence step:
Cloning a template is copying the text and pasting it into a new template. Any adjustments made to the text within the sequence step will not be reflected in the master copy of the template text.
Linking the template will link the local template to the master template. Any changes made to the template locally within a sequence will change the master template throughout Outreach. It also keeps the statistics on opens/clicks/replies consistent throughout the platform.
If you accidentally link a template, when you meant to clone, there will be an option to unlink at the top of the compose window.
If changes were saved to the linked templates, prior to unlinking the templates, the changes will still be reflected in the master template copy.