Call 1-800-MARRIOTT and they will add the MR# to your reservation. I did it a couple of weeks ago on an exchange into the Surf Club for next year. Got a newbie and he was unaware that the MR# could be tied to non-hotel ressies, and had to go to his supervisor to do so. My ressie now says I will receive credit for the stay.
We just got back from 2 weeks at the SC last month (again on an exchange) and received credit for the 2 week stay. DH is now well over the 75 days for the year and will be platinum elite again next year

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