I think we will see a 20xx refresh fairly soon actually, end of q4 2019 or q1 2020. My reasoning is that their original design target was 7nm, not 12. They backported a design to 12nm to get viable yields, cost, time to market etc. But no way they just stopped working on the 7nm design. They're certainly using that as extra time to refine and enhance the existing 7nm design.
IMO the wildcard is whether they hold back the consumer version of it to recoup on 20xx and only release the 7nm refreshed version for professional lines for 6+ month. This is the lever that might be pulled by competition, but the design work is certainly independent