I've configured branch.io deep link and all options as explained at dev.branch.io/getting-started/universal-app-links/overview/
I've setup corresponding configuration on the XCode side of things as well along with SDK integration as explained at https://dev.branch.io/getting-started/sdk-integration-guide/guide/ios/
I've validated the universal link using the tool and script provided on the page at https://dev.branch.io/getting-started/universal-linking-validator/
All tests run positive.
I'm also able to successfully launch the app from the deep link pasted in my Notes app, if I build and install in debug mode directly from XCode.
However once I distribute the build through test flight, I'm not able to launch the app successfully, it always takes me to App Store.