Per my understanding, this is based on certain model at certain time of the year. I guess dealership has the flexibility to determine which model is eligible for it. All we need to do is to ask for it when shopping around.
Yeah usually cars with that much time on the lot are on a hit list and no “reasonable“ offer will be refused.
What “reasonable” is depends on a ton of factors but the most obvious one past time since arrival is target incentives. Middle of month is a good time to start a dialogue.
What would the deal have been with 36 months? I would likely have done that, even with a few dollars more per month, since the deal would be hard to replicate in 24 months. And you have other up front fees on the next car, disposition if not getting another BMW etc.
On the other hand, you may not need new tires. But those can be had used for lease returns.