Originally Posted by YOWgary

No, you won't just get to pick any AC flight for free.

To make a long story short, the seats that were available under the old Aeroplan rules were essentially the same inventory that AC makes available to partner programs under the new program. This inventory is referred to as fare class "I", and a whole lot of what you see offered through Aeroplan at variable pricing, is in fare classes other than "I".

The simplest way to search for this space would be using the United website; almost anything you can book there as a Business Saver award should be compatible with the old-school Aeroplan rules.
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