https://princeoftravel.com/news/aero...s-to-bookings/
A new feature has appeared on some Aeroplan bookings, which allows you to make self-serve changes online instead of phoning the Aeroplan Contact Centre.
While the feature is currently being tested in beta mode and isn’t available across all bookings, it’s a very welcome development for anyone who has faced long hold times to make an amendment to a booking.
Full disclosure, it's not working for me on any of my bookings, but all my bookings either have a Priority Reward or Flight Reward Certificate.