2 Tweets from: Telecom;

1st:
We will be crediting new XT pre-pay customers for what they have paid for any of the Extras (SMS and data) between May 29 and May 31.

2nd:
We will also be putting in place a process that reflectes a more pro-rate approach in the future, thanks for the fedback - its usefu :)

Not sure how they differentiate this between pre-pay and post-pay customers...