Rear window not available

Hello together, I hope someone can help me here or has had similar experiences. I drive a BMW 840i Gran Coupé, which I leased. Unfortunately, two weeks ago the rear window bursted. Since then, the car is at home in my garage and is not usable because the disc is not available. My dealer has ordered the spare part directly, but the status is “Reserve” – which probably means that there are currently no reliable delivery dates. D The whole thing has been going on for two weeks now, and to be honest, I’m a little frustrated. Without the car, I’m dependent on alternatives and so far I don’t have a clear statement from the dealer about when the vehicle will be ready for use again. Does any of you have experiences with a similar problem? How did you do in such cases? Are there any ways to exert more pressure on BMW or the dealer? Would you be very grateful about any advice or experience report. No, no, no, no, no, no, no, no.