According to Foresight News, the Cosmos Hub community has initiated a proposal for the 'Gaia v16 software upgrade'. The voting on this proposal is set to conclude on May 10th. The proposal indicates that the Gaia v16 version introduces the ICA Controller submodule and the IBC rate limit module. These include the initial rate limit outlined in Proposal No. 890, the IBC fee module, and ICS epochs, which are part of ICS v4.1.0.
Before the Cosmos Hub upgrades to the final version, validators and node operators have joined the public test network to participate in testing the upgrade to the candidate version. Once the governance vote is passed, validators will need to update the Cosmos Hub binary files at the stop height specified in the on-chain proposal.