The Taiwanese foundries are already building a new R&D center for 2 nm technologies and beyond in Hsinchu, which should be ready some time in 2021. The exact timeline for the 2 nm volume production is not yet known, but TSMC reports that it has been collaborating with some of its customers on the development of this advanced node. Market analysts claim that Apple will be first to launch 2 nm SoCs thanks to a five-year production deal with TSMC.
https://www.notebookcheck.net/TSMC-hints-at-securing-Apple-SoC-production-deal-including-2-nm-chips-for-the-next-5-years.489668.0.html