Here's a little teaser....

[s7e9h3n]

AMD officially uses the expression "Stepping BA" on its site:
http://products.amd.com/en-us/OpteronCPUFilter.aspx
but yeah I think that it may differ from CPU-Z showing.
On Anandtech, K10 2.5GHz ES shows stepping 2 on CPU-Z,
and revision is grey-out.
I suspect 2.5GHz ES may be "Stepping BA", only just speculation.

Anyway I still have a little, a very little hope for newer stepping & BIOS

No, the 2.5G Phenom from Anandtech is a stepping B2...I'm positive of that

EDIT: Oh yeah, and in regards to the BA stepping - I stand corrected. But one thing is for sure....AMD doesn't list ANY cpu's on their site if it doesn't reach production levels. If you can find it on the site, it means that they're officially being produced.....