When you currently try to update your vCenter Service Appliance (VCSA) 6.5 in Virtual Appliance Management Interface (VAMI) (Port 5480) your only suggestion is Update 2. A new feature of VCSA 6.7 is the ability to select the update you want to install. In 6.5 the latest update will be installed when using default repository.
vSphere 6.5 U2 is a very uncommon update-version. First, there are not just fixes and updates in U2 but also new features (see here) that are also available in vSphere 6.7. Second, U2 gets available after 6.7, so it is not possible to upgrade 6.5 U2 to 6.7 GA. Therefore updating to U2 should be well considered.
What are your options to stay within a Update version respectively select your update version?