ISO to MIP?

My company has been acquired by a PE firm (majority stake). 

One year of the four year cliff has vested from my options, which we'll be getting a payout on imminently. That's the good news. 

The final three years have been cancelled and terminated, and will be replaced with a "Management Incentive Plan."

Does anyone have experience with this situation, or any guidance as to how an MIP pays out comparatively to traditional options? Especially for someone that's still an individual contributor? Thanks!