I'm not participating in the 100K promos, but I thought this might be of interest to those who are.

I took and AA flight in October, and because I was in such a hurry, forgot to give my CP number. I dropped off the boarding pass and required paper work at the CP office in Vancouver on Dec 3. The flight appeared on my account sometime between Dec 14 and Dec 18.

So it appears that CP is taking about 2 weeks to post any boarding passes that are mailed in, not including the mail delivery time.