User durberville reports on the Milesbuzz! Canada thread that he/she had originally taken the 15,000 point offer, and was able to get a phone rep to add 5,000 points to the account.
If you also took the 15,000 offer, be sure to call before August 31! The 20,000 point offer is likely to end on or before that date.
Post:
http://www.flyertalk.com/forum/21336250-post110.html
Full Milesbuzz! Canada thread:
http://www.flyertalk.com/forum/miles...-canada-8.html