The company announced Zen+ cores in 12nm that are expected to ship by early Q2 and replace the current Ryzen 7 stack, but the fact that the one after that is finished, brings a degree of certainty that we might see the Zen 2 designs next year.
This is when 7nm becomes a bit more mature and companies like Apple, Qualcomm and Samsung will help in the process. They will drive millions of mobile chips through the fabs and help the AMDs and Nvidias of the world refine the yields for higher complexity and bigger chips such as GPUs and CPUs.