Carried Interest: Sunset or expiration after vesting?

So my firm is looking to change their carry program to include a sunset clause on carry. Meaning, even if fully vested if you leave the firm the carry is no longer paid out. A) anyone else see an expiration or wind down of carry in PE or VC? B) how would you respond to having previously awarded carry (in lieu of cash bonus) that originally had no expiration but did have vesting, going through the 3-4 year vesting period, and then being told retroactively that the plan is changing so if you leave you forfeit it all.