New Generations Voyager Cases have arrived at BBTS, with two Brainstorms, a Whirl and a Roadbuster... but their single Brainstorm listing is still listed as "pre-order" so it doesn't look like they have broken up any cases yet.
Hopefully it is just taking them a day or two to break open cases and distribute the Brainstorms.
But in case they don't or if you are desperate and can sell off the other three toys, the cases are now available for sale.