One of my fellow bloggers Michele posted a while back "Once A Black Belt...Always A Black Belt?"
In a nutshell, she asks if one attains the level of black belt and then stops training for whatever reason, are they still a black belt, or if the rank stops if the training stops. The title of this blog was taken from a sign that hangs in the dojo at the PaSaRyu headquarters in Cordova, TN (right outside of Memphis, and I suppose kind of supports my answer to Michele's question.
To make this a bit easier, I'd like to compare this to a personal story of mine. After all the years going through grade school, junior high, and finally high school, I decided to go to college and earn a degree in music. After four years of study, various assignments, tests, projects, etc., I received my Bachelor's degree in Music. In the years since, I haven't attended a single music class, studied anything from Bach to Beyonce, nor (outside of maybe a combined 2-year stretch of piano playing at church) have I done anything else musically inclined (and at this stage, probably never will), but for whatever reason, I'm still a college graduate with a Bachelor's degree in Music (I even have the piece of paper given to me by the President of the college to prove it!).
Referencing back to that sign I mentioned earlier, Master Kang Rhee says that a black belt is for life, and once gained, no one can take that away from you, just like that college degree. Once you've paid your dues and earned that rank, it's yours...for life.