Starting with VMware vSphere 8.0 the release model has changed with a new Release Model to encourage the adoption of vSphere releases. 

VMware is moving to a new IA/GA (Initial Availability/General Availability) model to ensure our customers have all the information and lead time they need for successfully adopting and consuming the new releases.

“An IA release is a production-quality release that meets all GA quality gates and is fully partner certified. IA releases will be available during the IA phase to all customers for production deployments. We will follow up once we determine each release has achieved sufficiently wide adoption and announce the transition of the release to a GA designation.”

For more information see: The vSphere 8 Release Model Evolves.