Ok. I wouldn't panic here. Calm down.
How shares are vested is up to the board. So, if this were to pass I would just walk into the CEO's office with a few employees and ask to change how shares vest to: "Upon the vesting schedule AND a written letter from the employee requesting vesting. If the letter isn't submitted the shares are not vested." So, if I don't send a letter to the board the shares do not vest. If I want to vest 12 months and leave, I would just submit the letter. Problem solved. How shares are vested is totally made up. You could have them vest when you wear a purple shirt on tuesdays.