bri@screwtape gotcha! i'm not a lawyer so... y'know, grain of salt, but i can tell you my understanding. cc licenses are irrevocable. but, as the rights-holder, you are free to 'rerelease' such a work under a more- or less-permissive license. you can freely attempt to scrub all instances of the earlier version if you so desire. but the irrevocability means that if someone has a copy of the version that was marked cc 2.0 out there, _that is still binding_.
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