Hi, Nikolay
Why not?
I seen F7.x and F6.x succesfully work on VCS x7 and x6.
In all release notes tandberg & cisco to point the last and sometimes next to last software for their devices.
In my network succesfully work some ancients T150 (but they absent in RN) and F8.3. with VCS X7.0.2 TMS 13.0.2.
You can read the release notes for F9. Maybe there are new features for yourself?
br. Oleksandr