No, there is no automated way to move from CentOS-6 to CentOS-7 .. and we have no idea what will be in CentOS-8 until Red Hat releases RHEL-8. We have no idea what will be in CentOS-6.11 until Red Hat releases RHEL-6.11 .. and we have no idea what will be in the release of CentOS-7 until Red Hat releases RHEL-7.6 .. literally, we take the source code they release .. modify it for Trademarks and Logos .. and release it. Until it is released, we don't have a clue.
This is in the RHEL 7.6 Beta Release Notes:
Part I. New Features This part documents new features and major enhancements introduced in Red Hat Enterprise Linux 7.6 Beta.
Chapter 4. General Updates In-place upgrade from Red Hat Enterprise Linux 6 to Red Hat Enterprise Linux 7
An in-place upgrade offers a way of upgrading a system to a new major release of Red Hat Enterprise Linux by replacing the existing operating system. To perform an in-place upgrade, use the Preupgrade Assistant, a utility that checks the system for upgrade issues before running the actual upgrade, and that also provides additional scripts for the Red Hat Upgrade Tool. When you have solved all the problems reported by the Preupgrade Assistant, use the Red Hat Upgrade Tool to upgrade the system.