I joined Lifemiles and tried the same dates showing not available on Aeroplan and indeed they were available there. I called AE and was told that Copa has been down since March 20th and Aviance since March 29. It is an IT linkage problem with their respective airline systems and while they are working on it there is no update as to when it will be fixed. Furthermore, I was told that not all airlines release their reward seats to AE or other *A airlines at the same time as they are available on their own home sites. So checking a home site does not mean AE or other *A programs will have access to those seats.

Just have to wait I guess