There are a lot of changes done on SPINNR v3 and WPTheme v3.4.0 so migration will not be straightforward. This documentation is here to help you with the migration. The steps are listed as follows:

1. Create a backup of the old site. Save an HTML copy of the header, mobile menu and footer from the browser. You might use this later to update the header, mobile menu and footer.
2. Upload the new theme. It should be >= v3.4.0
3. If you have template overrides, remove the following files from the child theme. If you have customizations, you would need to take note of them and apply them later in the new header/footer
   1. header.php
   2. footer.php
   3. template-parts
4. Run the setup process to create a new project in SPINNR. Ensure you are using an administrator account and registering the same email address. This will automatically be added to Domain and Credentials.
5. Check and update the Brand Style Guide.
6. Update your header, footer, and mobile menu in SPINNR. You will find it easy to copy and paste the HTML directly and replace it with existing.