I don’t have any advice, but can tell you my experience. Within the last 2 weeks, my husband and I both had our Disney Platinum matched with Diamond. HOWEVER, in the next couple weeks Disney will be adding the new Pearl tier to be above Platinum. I’m not sure how that will impact what MSC will match the Platinum to, if we assume Pearl will be matched to Diamond. I wish I could be of more help, but as of last week, Platinum did match with Diamond. I have never sailed NCL, so cannot give opinion on that.