The release notes for 7.0 do not include the section titled "Verify the version of the deployed Agent software", which is where past version release notes listed the minimum agent version required before upgrading. To avoid loss in agent communication, it is necessary to confirm that the agents are at the minimum required version. Though older versions may still communicate and upgrade properly, they have not been fully tested and are not supported should they lose communication after an upgrade. This is especially noteworthy when upgrading a K1000 that is multiple versions behind.
The minimum required (tested) agent version for upgrading to the 7.0 version of the K1000 is agent version 6.3 or higher.
Please note that since 6.3.306 agents have been known to cause temporary performance issues on reboot, it may be best to make sure they are at 6.3.314 before upgrading to ensure optimal performance.