Is there a best practices guideline for how I should add custom code while using the SDK to ensure that nothing, or as little as possible breaks when I do an update to a new SDK?
Aside from release notes does Cypress provide any other guidance on how best to update to a new SDK to limit the impact to custom code?
Recommend you add additional head file and .c file for all of customize function and defines. And add into the SDK example project and use Marco define. When you have to upgrade to next version, You can just make those changes and search with MARCO define. And the version management tool is recommended.