Originally Posted by
GumshoeW12
No, it’ll be up to the cruise line to process emigration documentation, as the airlines do when you fly.
But you’re right to assume that a one-way ticket may well lead to extra scrutiny on arrival.
Cunard will arrange J or even F for you upon request but when I asked them for prices a while ago they politely requested I pay through the nose, hopefully the OP has better luck.