The USB4 specification was finalized in September 2019 and rumor has it that AMD's next-generation Ryzen processor will support this standard. New reports indicate the Ryzen 4000 series and 600 series chipsets will support both USB 3.2 and USB4.
There is also a rumor that the next generation may use a new socket due to support for new technologies. Personally, I'm not sure if we're already going to see this for the next generation but it's in-line with AMD's promise that it would continue to use Socket AM4 through 2020.
AMD will have a flagship X670 chipset, something that will continue to support he AM4 socket and PCIe 4.0 standard, but we could also see native Thunderbolt 3 support included. Other rumors do state that AMD could shift away from the AM4 socket, but that would be a big shift -- it would end backwards compatibility, but it could introduce new tech like DDR5 and PCIe 5.0 standards going forward.
The Ryzen 4000 series is expected towards the end of the year.