The whole point of CoreOS Container Linux was to deliver a steady stream of security/software updates. We've been eager to update packages for Flatcar Container Linux but have wanted to maintain as much compatibility as possible for as long as possible. Fairly soon, however, we'll be introducing an updated kernel and user space (systemd, Docker, etc.) into the alpha channel. For us, this will mark the point where we feel like we're fully taking the reins from CoreOS and carrying forward the original objectives.