I have done 22 cruises and asked a crew member if I become Pearl on my 25th cruise or after I have completed my 25th cruise. They said ON my 25th but I am not sure I believe them.
Directly from the DCL website "Disney Cruise LineCastaway Club recognizes Guests who have completed 25 or more sailings as Pearl Castaway Club Members." I bolded the completed part, you will not be platinum until cruise 26.
Consistent with moving between other levels, you should become Pearl as soon as you disembark from your 25th cruise. When you plan for your 26th cruise, you can book as a Platinum Castaway Club member.
I got an entire platinum package and an entire pearl package during that leg of the cruise. This was our third cruise in the B2B2B so I already had two platinum packages. Between the CC gifts, the halloween package and the romance package, I had to purchase a suitcase to get everything back home!
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