Once again Micasaverde is confusing users…only this time for a positive change to UI4.
1 - My Vera 2 says it has the latest firmware (1. something with UI3).
2 - There is an official post, announcing the exchange program to a vera 2 with UI4
3 - The users posts in the UI4 forums confirm the link to UI4 has been removed because it was still beta.
It is becoming really tiring to try and understand what’s going on here… of course, if UI3 had been more efficient, users wouldn’t be struggling through the forum to finally know when they can get rid of it ;D
UI4 hasn’t been made “widely” available yet.
It is being made available, in limited exposure, via a “note” in new Vera 2’s going out. This is done to ensure that all issues are fully ironed out before a “mass” upgrade occurs.
Oh, and apparently the Kwikset Lock needs UI4 for it’s full functionality also, which is part of the driver as well.
The Vera 1 → Vera 2 exchange program is somewhat orthogonal in nature. I’d expect these will also come with the same “bit of paper” with UI4 instructions, but that’s a guess 
When UI4 is made available to the masses, there will be an Official Post, in that section of the forums. All other “notes” are from end-users, and should not be used as a source of truth for UI4 availability - no matter how tempting that might seem 8)