July 1, 2021.  The PCI Security Standards Council (SSC) recently announced that it now anticipates a Q1 2022 publication date for the new PCI DSS v4.0 specification. This date adjustment accommodates an additional request for comments (RFC) period on draft PCI DSS 4.0 validation documents. Comments are currently being accepted from stakeholders, including merchants, gateways, processors, device manufacturers and others.

Potential commenters can find the documents at the PCI DSS Official Site.  https://www.pcisecuritystandards.org/document_library