just got my e-mail today and this is what they said
"We are contacting you following your recent claim in our Stella Artois Free Belgian Chalice Glass on-pack promotion.
We're sorry to advise that, as a result of a number of fraudulent entries, and to be fair to those of you who have participated in the promotion in good faith, we now need to verify all entries into this promotion.*
In order to verify your entry, please have your two promotional packs to hand and call our helpline on 01296 within one week of receiving this email. Lines are open Monday - Friday between 9am and 5.30pm - standard charges apply. Following your call, please be prepared to send the two original codes to our Freepost address.
Thank you for your understanding, and we look forward to hearing from you soon!"