Bizarrely, this means South Dakota now has two separate Abyssal forms (and yes, they are counted as separate on the Kancolle wiki): this one and New Southern Battleship Princess.

Historyanon said in comment #2616354:

Bizarrely, this means South Dakota now has two separate Abyssal forms (and yes, they are counted as separate on the Kancolle wiki): this one and New Southern Battleship Princess.

Thought she was the same girl but with a different outfit (similar case as say Aircraft Carrier Princess and her summer version) BUT her voice sounds pretty different.