Activation codes expire on their natural expiry date
Instead of expiring after three months, unused licences now expire on their natural expiry date according to their initial duration. In other words, if you receive a twelve-month activation code, it will expire twelve months after its date of issue regardless of whether you activate it or not.
Too late for me? No, you just got your activation code back
And this applies to all activation codes ever issued. So if you received a twelve month activation code four months ago, which therefore expired last month, it just came back to life and will expire in eight months’ time whether you use it or not.