It happened to me last year.
I have received an envelop from SQ with gold card inside. I was totally as my mileage at that time was around 38,000.
I have posted a thread at that time wondering if anyone experienced the same/similar thing.
As a holiday flyer who fly only twice a year and no deisre to become KFEG, I have no intention to try to keep my status.

As some experts suggested, if I may, also reccomend you to take an advantage of earning 25% extra milage while you can ^