If you have a component or flow function in your app that has a static array type property binding, such as the options for a dropdown, and you switch the binding type to formula function, a subsequent save will fail.
This is due to a bug in the JSON patch library we were using and will be fixed in the next release.
To circumvent this, you can either remove the component, save, and then add it again, change the binding type and only then save. Alternatively, switching the binding type to a direct variable binding, saving, and then switching to a formula binding and saving again works.