In Star Trek Beyond, there was a ship under construction on the massive
moon space station Yorktown. This ship is rechristened as the USS Enterprise-A (NCC-1701-A) after the USS Enterprise (NCC-1701) is destroyed. In the original timeline, the ship that became the USS Enterprise-A was the USS Yorktown, but in the new timeline, the space station is called the Starbase Yorktown instead. Of course, the original concept by Roddenberry for Star Trek had the ship named the Yorktown before changing it to Enterprise.
So what was the ship in Beyond originally meant to be registered and named? And is it also a Constitution class ship?