Not yet. We could make it bindable but I think it’s part of a larger discussion we have around environment variables.
I dont want to make it bindable because it could prevent us to change the way it work, if we want to introduce a new kind of secure field to manage credentials.
I know it’s a blocker in the meantime as there is now way to configure a different URL and public key by environment so it should be prioritised asap imo, I will discuss it with the product team 
Edit : Actually, we cant make it bindable because we need them also in the backend when checking the page access, and formula can be evaluated only in the frontend, so we will have to release this new feature to allow such use case (different instance per environment)