Will I no longer have Platinum Elite status if I haven't achieved 50 nights by 31/12/2018?
From the T&Cs:
To achieve or renew Elite membership status, the following number of Elite Night Credits (“Minimum Requirement”) must be earned through nights stayed at Participating Properties or (ii) Rewarding Events between January 1 and December 31 of any given year:
The complete T&Cs:
Terms & Conditions | SPG & Marriott Rewards
So the answer is yes.
You have until 31 December to reach 50 nights to retain your Platinum status. If you don't, when Marriott resets status (the end of February, if I recall) you will lose your Platinum in status.
Best thing is to check with communitymanagers or the Rewards Customer Services as to validity of your Platinum status. In a recent conversation with Customer Service, I was informed that my Plat Prem status is valid through to Jan 2020.
I also see similar information in this post
The annual reset might be the beginning of February not the end (my recollection may be off slightly). It's been a few years since I last failed to retain my status, though I thought the last time it happened to me, I thought it was the end of February (2014).
One date is certain, you need to hit 50 nights by 31 Dec to be Platinum beyond the first month or two of next year.
I could be wrong. Based on a few anecdotes, it seems if one achieved Plat Prem this year as part of 'the legacy > new programme mapping', then validity of that status has been set to Jan 2020 regardless of the number of nights achieved in 2018.
That makes sense. If someone achieved any level during 2018, that status would carry over until the end of 2019 and into the beginning of 2020. If, however, someone previously earned a specific level in 2017, that level would expire in early 2019. With the changes to the program and the way legacy levels were mapped to the new levels, everything could be a bit different this year. It's definitely worth a call to the Rewards line. They'll be able to tell you when your current status expires and what you need to do to retain it for another year.
Normally, if you don't have enough nights to retain your status each year, you will lose it. That's another reason Lifetime status is so important. Once you have it, you get to keep that level without having to re-qualify each year. Also in the past, Marriott offered what they called the "soft landing" meaning you could only drop one level regardless of how few nights you stayed during the past year. There have been reports this is going away, but I'm not sure it that has been confirmed.
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