v1.10.11-mev0.4.0 is a hotfix release to catch up with the latest changes of go ethereum. It includes all the changes from our last base v1.10.8 to the latest release v1.10.11. See the upstream geth releases for details https://github.com/ethereum/go-ethereum/releases.
There are no new Flashbots related changes since the last release, besides a new link in the README.md file.
Everyone is advised to update as soon as possible.