HCS Release Numbering
The current release number for Cisco Hosted Collaboration Solution is 12.5, and the latest release is called HCS 12.5 Add-on 1; future solution releases will be named by increasing the "add-on" number.
Cisco HCS releases are numbered so components of the solution (eg., Cisco Hosted Collaboration Mediation Fulfillment) are given a tertiary release number that descends from the solution release number. For example, HCM-F 12.5(1) is the initial release for that component; subsequent releases are numbered 12.5(2), 12.5 (3), and so on until the next solution release.