They will know already. That's why PM wants the port to be done at the same time as the activation. There is nothing else you need to do to indicate you were a Freedom customer. Simply check your account for the extra 6GB. If it's not there in 3 days, then private message a moderator about it.
As per the details on the promo page, the extra 6 GB will be automatically added to your account within 3 days of your activation, as long as you've ported a number in from Freedom at the same time.
