Not sure if this is how it's meant to be or if I just got lucky but I was looking for a way to get out of my lowest reward economy ORD-YYZ ticket (AA $$ price went down)
Didn't want to pay the 150 CAD so decided I'd just stick with it. But, business miles went down so "upgraded" to Business Lowest for additional 10k miles and 10 cents. Just for fun I clicked on cancel and it showed a refund of taxes and fees and all miles back so I was able to get that back and book my new AA ticket