References to AMD X590 chipset were spotted in the BIOS code of a Gigabyte motherboard by a user on the Computerbase.de forums. This follows the tease of X590 by known Ryzen enthusiast Yuri Bubly on Twitter. Not much is known about the X590 platform but speculation is that it could feature even more number of PCIe Gen4 lanes than what X570 offers.
https://www.notebookcheck.net/Rumored-AMD-X590-chipset-touted-to-offer-even-more-PCIe-4-0-lanes-for-premium-Ryzen-3000-CPUs.424007.0.html