The Polaris 30 might come as a surprise, but AMD also neglected to mention the Polaris 20 GPUs in last year's roadmaps, so this looks to be business as usual for the red team. With a rumored 15% performance increase, the Polaris 30 GPUs will be comparable to the RX Vega 56 GPUs. AMD is also said to be preparing budget 7 nm GDDR6 GPUs for early 2019 and high-end HBM2 variants for late 2019.
https://www.notebookcheck.net/AMD-Polaris-30-12-nm-GPU-coming-in-Q4-2018-7-nm-gaming-GPUs-coming-in-2019.313716.0.html