Cardano released Node 9.1.0, a significant step toward the Chang Upgrade. This upgrade comes before the much-expected hard fork. Node 9.1.0 serves as the mainnet candidate for Chang Upgrade #1. This new update introduces governance features and initiates the CIP-1694 Bootstrapping Phase.
Earlier this July, Node 9.0.0 was launched to handle the Chang hard fork on the mainnet and testnets like PreProduction. Node 9.1.0 introduces a significant change: a Conway genesis file is now required at startup to bridge the hard fork border.
It also includes bug fixes and upgrades to the CLI and API, such as the "query treasury" command.
Cardano recommends that all Stake Pool Operators (SPOs), exchanges, explorers, and wallets upgrade to Node 9.1.0. After enough SPOs and exchanges have been updated, an updated proposal for the Chang hard fork will be released.
The Chang Upgrade will introduce phased governance features. This new feature will make it easier to onboard new governance roles. Chang Upgrade #2 will finalize on-chain governance functionality, such as DRep participation and all associated actions.