I’m currently on a cruise ship, and received notice that onboard charges would be processed through a UK bank, but would be charged in dollars. The ship said that if we wanted to change the card on file to let them know.

Initially, I ignored the message, but started wondering whether this would somehow be a DCC situation, and whether I should change my card on file from JP Morgan to Amex.

Sound like a disguised DCC to the experts here? Suggestions?

Many thanks.