If it happens theres nothing anyone can do about it, and it wont cost anyone anything, and everyone knows it. but you are spending way to much time gazing into a crystal ball and writing about it pessimistically.It also doesn't cost anybody anything to prepare for the possibility that an 'exception' product such as the fee free for life Signature card is not transitioned over.
there is zero reason to assume that NAB will migrate Citi products into their own, or vica versa. the presentation indicates its new products and innovations.