As an update. I'm taking my car in for the 2nd free oil change (~15k) next thursday to Sterling BMW in Newport Beach, CA. I've given the dealership a heads up about the problem... though the SA said he's never heard of the issue.
However, it appears that a mechanic who works at the dealership vists this forum. I've sent him a PM asking him to look take a look at this thread and help me resolve this issue. Will keep you all informed of what, if anything, comes about as a result.