Presumably what they want to do is mix the BSD code with their own code and release the whole under a restrictive licence. That's permissible under the BSD licence, but doesn't involve relicencing the BSD code, since that's still available under the BSD licence.
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Presumably what they want to do is mix the BSD code with their own code and release the whole under a restrictive licence. That's permissible under the BSD licence, but doesn't involve relicencing the BSD code, since that's still available under the BSD licence.