Based on a couple of posts over at BlackBerryForums, it appears that T-Mobile (UK) is preparing to release a new OS version for the BlackBerry Bold (9000).  Keep an eye out here for the announcement and link.

Midnightdraven asked:
SO, I get an email today that there is new updated software for my phone.
Ok. so I check first t-mob’s uk download for OS’s. Nothing new.
Plug my phone into my pc, go to the bb.com/updates site, click update, get app loader up and it checks and shows
4.6.0.162 Downgrade
4.6.0.216 Current
4.6.0.291 Preferred

What I dont get is, this hasnt been released by my carrier, (or they havent updated their site) and yet it automatically shows this for my carrier.
And we know the latest here is .282.
So, whats going on?

Should I update?

JSanders answered:
If you’re getting the upgrade bump from your carrier, the your carrier has released it. Its not uncommon for the wireless update to come a few days or couple weeks before the manual update file.