Originally Posted by
yyznomad
Nitehawk
Are you 100% sure it was
actually an SDC?

Not sure how they did it. I specified SDC and I wasn't charged for the change (which I believe aligns with the fare rules).
I have an interesting datapoint. I SDC'd two segments of a three segment trip (in one direction). The third segment which was flown one day later than the SDC'd segments has now posted to Altitude/Aeroplan; the SDC'd segments have not posted, despite my BPs properly showing my altitude status.