It appears CVT owners can get the EPA numbers. 8 people have posted at:
2012 Impreza 2.0 with CVT.
low of 25 high of 36. Average of 29.8mpg
Without looking at each one individually, I doubt anyone of them is 100% city or 100% highway. So in general, the average should come out near the EPA Combined MPG.
I have over 14,000 miles on my CVT and typically get 32 to 36mpg. While never getting less than 30mpg calculated and driving with the flow of traffic.