What happens to prior year inventory if unsold?

My thought was to wait out dealers with alot of 2016 EV’s (soul) that can’t get 17’s until they sell the 16’s. I figure they’ll be more motivated towards the end of this month. There’s 100 available (all black) within 100mi radius. If a dealer has 10 or so on their lot do they usually have to sell them all or do the unsold end up somewhere else at some point? I’m trying to avoid missing the point where they’re the most motivated.

They lose a ton of money to sell them.

The manufacturer will drop all the rebates are apply ‘final pay’ monies.

It varies between the vehicles.

Any idea when that could occur or what pct ‘final pay’ is (with Kia)?
Let me try an example so I’m understanding correctly “on 4/30 Kia will drop 15k rebates on '16 soul ev’s and apply 20k final pay towards 38k msrp for dealer to price low enough to sell?”

Never has there been a 20k final pay. I wish!

It’s probably <$7k