How can I get firmware 2.9?
Seems that entry in release notes has been added but package didn’t reached the repo…

Why I have upgrade option available when 2.8 is current version running on my box and last available version is also 2.8??
Not knowing the details of how upgrades are released, my speculation is that 2.9 is not really released yet. Maybe they were about to release it, so it got into the notes, but then an issue was found and the release halted. Just a guess…
My crs328 has been reporting this for some time, there appears to be error in the update server info