With the 4.x SDKs you will be responsible for creating the bridging headers yourself. We do not have engineering support for React-Native with the 4.x SDKs. We are also completely ending support for the 4.x SDKs a year from now. Using the new React-Native SDKs allows for a lot of flexibility. You can use Adobe Launch for server-side configuration, which allows the customer to deploy changes on the fly. There is also the ability to use the Launch rules engine, 3rd party extensions etc.