A/D what I mean is that when you schedule a service update for the vehicle a hot spare with the latest updates should be overnighted to the dealer or sent ahead of time and be waiting for the vehicle to arrive.
This would minimize downtime to a simple swap out and eliminate the point of failure that seems to be recurring. No more he said she said--just BMWNA.
They then replace your old DME with the new one and send the out-dated one back for bench testing, newest update, burn in period, then recycled to the next out dated vehicle.
This raises the level of quality assuarance along the whole custody chain.