You are correct. Your elite level will be valid for the rest of the year that you earned it (even if through the rolling-year cycle), and all of the following year. So if someone achieved Plat elite status on Feb. 20, 2007, then they would be a Plat through February, 2009. (Note that Marriott's elite levels don't expire at the end of a year, but at the end of February the next year.)