Per an Industry Alert from the USPS® on March 13, 2019:
The USPS is evaluating proposed changes to addressing policies that will have an effect on Coding Accuracy Support System (CASS)-certified address matching software. Due to the need to review, develop and document these new addressing-related policies, the USPS has decided that a revision to the current CASS Cycle “O” implementation schedule is required. Originally scheduled for an August 2020 release, the new scheduled implementation of CASS Cycle “O” will be August 2021.
USPS will release updated requirements for CASS Cycle “O” once finalized. For additional questions you can contact CASS support at 1-800-642-2914 or email firstname.lastname@example.org.