The point is that there is a build queue. so you need to find out where your order will fit in to the Munich factory build schedule.
I ordered my F30 335 MSport Xdrive at the end of June 2012 and got a build date for the week of Sept. 17th, approximately a 12 week lead time. I was then able to firm up travel plans for arrival in Munich on Oct. 8th and a delivery date of Oct. 9th.
I would not book flights and hotels until the build date was known, as you run the risk not being able to find a reservation notwithstanding the fact that changing reservations is expensive.