Originally Posted by
alexthe5th
Precisely my question too. If a flight departs on the 31st and arrives on the 1st, how does that work?
Intuition tells me that it's based on
scheduled departure time. Then again, intuition's failed me so many times in the past with Aeroplan...

AE should be fine for departure date. I had a Hyatt stay on August 31st with a check out the next morning on September 1st -- overnight of a MR to DFW actually -- so didn't expect it would earn credit for its Faster Free Nights promo that started September 1st. However, much to my delight, upon my second Hyatt stay I noticed I got a Free Night credit from the promo as it seems Hyatt bases its promos on the date of check-out, not check-in!