https://wccftech.com/amd-allegedly-delaying-ryzen-4000-series-zen-3-cpus-to-2021/

Word out of Taiwan is that AMD has decided to delay the launch of its Zen 3 based Ryzen 4000 CPU series from September 2020 to early 2021. This is not because of any technical difficulty but simply due to consistently strong demand for Ryzen 3000 series and lack of competition from Intel. Considering the magnitude of this leak and because it contradicts earlier reports, we have marked this post as a rumor. Caution is advised. That said, Digitimes is one of the most reliable newspapers in Taiwan when it comes to tech and has extensive industry sources so this might just turn out to be true regardless.

According to earlier reports (and the official roadmap), AMD was planning to shift to the 7nm EUV process from TSMC with its Zen 3 architecture by the end of the year. This would have absolutely cemented its place in the x86 market and led to significantly increased market share. It would also have made Intel offering completely uncompetitive (at current pricing) as its 10nm HEDT parts aren't expected to ship this year. Interestingly, Digitimes believes that Intel will not be able to ship 10nm in volume this year either and because of this AMD will be delaying their 7nm EUV launch to CES 2021.