I first got my Surpass card in September, 2011. I was given Gold and expected it to be valid through March 2013. Instead, it was valid through March 2014.

In mid 2012, I put $40,000 in spend on it and was made Diamond. I received a card which expired, as I expected, in March 2013. Today, however, I received a new card which keeps me at Diamond through March 2015.

(I have had no stays yet this year and very little spend on my Surpass card.)

I am trying to figure out how long status is valid. I thought it was for the year you earned it, the following year, and through March of the year after that. However, both times I received it for the year I earned it, two years after that, and through March of the following year.

Is this always the case? Is it always true for Surpass but not for status earned by stays or points?