If you get the 10 day message, it adds a remark to the PNR that all agents can easily see. If they tried to charge a cancellation fee, the PNR itself is evidence that you made a good-faith attempt.

The remark looks like "MEMBER REQUESTED REFUND ON AEROPLAN.COM AND TRANSACTION FAILED. PNR QUEUED FOR REFUND TO BE PROCESSED."

Automatic refunds after multiple involuntary schedule changes don't work very well.