why not you let BMW change it for you, since it is covered under warranty?
Im Kinda against DIYing the bulb because, when you get your fingerprints on the bulb, it would shorten its life. Plus buying your own bulb out of pocket.
I had experience changing my headlight assembly numerous non xenon with cheep aftermarket headlight with halo's, it is definitely a dangerous job that we risk getting electrocuted :X
anyways Good Luck thu~