^ Don't get your hopes up. My car was the first production month BWM lengthened the brake fluid interval from 2 years to 3 years even though the brakes and fluid are exactly the same.
Your best bet is to continue paying for the halfway oil changes at the 7500-mile mark as you've been doing and I do myself. Someone asked about changing the VO to configure their car for the new interval. I doubt that would work without a software update since the older software probably wouldn't see that as a valid code, and even if a sufficiently new software revision were installed, it may reject that code based on the actual production month of the car.