Most people do not count Bridges a a new version. They gave the Enterprise-A a new bridge almost every movies. As for the Excelsior refit. That is coming. You can see it in space dock at Earth. T5 version all the way. A Excelsior refit fought the Defiant to stand still in DS9: Homefront. Yes the ship was updated with the newest weapons and Shields but that is the nature of Star Fleet ships going back to TOS. You can update them.