Thanks for all the inputs. I appreciated.
So I think I will use aeroplan website to do the main search and assist by United.
"emcampbe" mentioned UA doesn't list SQ award seats, how do I ensure I have all SQ seats available? Is there is a way to search award seats by airline? I would like to find out al available seats for FCO-TPE in August. Rather than checking day by day with aeroplan, is there a better way?