Was Cemetery ridge named for the National Cemetery that was created there months later? Or was it called that before?
I'm going to guess it was named due to it's proximity to Cemetery Hill which, itself, was named after the Evergreen Cemetery. Both of which pre-date the battle and the National Cemetary.
Cemetery Ridge contained Cemetery Hill which in turn contained the Evergreen Cemetery that served the city of Gettysburg.
In was (unfortunately) aptly named, because by the time the three day battle ended, it became a cemetery that "served" the whole nation, not just the one city. The National Cemetery was so named here for this reason. "The brave men, living and dead who struggled here have consecrated it far above our poor power to add or detract. The world will little note nor long remember what we say here, but it can never forget what they did here."