Because that's the grand plan from the start. You don't put a sentence like "In other words, upon a change in control where Tesla is acquired, vesting of milestones under the CEO Performance Award does not require the achievement of a matching Operational Milestone." if you didn't think Tesla could be acquired.
The goal is to give Elon his 2012 award package but making it his 2018 one.
Because that's the grand plan from the start. You don't put a sentence like "In other words, upon a change in control where Tesla is acquired, vesting of milestones under the CEO Performance Award does not require the achievement of a matching Operational Milestone." if you didn't think Tesla could be acquired.
The goal is to give Elon his 2012 award package but making it his 2018 one.