If it's not in the change log then it has not been implemented yet. I will do it when I get to it. I have one idea on how to implement it but I need to prototype it and see how it works in reality. As for custom bitrate: I will not be adding custom bitrate. It will be however possible to modify it by editing the configuration files to adjust it since I don't hardcode stuff usually. It will be overwritten though when a new release gets out.