When twitter will allow to release to get inactive or suspended username?

I am willing to get one username on twitter which I like very much. But when I try to register it says its already taken but when I visit its profile it says this account doesn't exist. I found somewhere at twitter's status like this:

Is there any date when twitter will allow to get ?

 

I know that they plan to release unused usernames but god knows when.

 

I really don't know when they're going to release those unused names, I really like few and would love to use them.