Thanks for the reply.

I fly enough on AC to make 35K (Star Silver). No real other benefits other than on AC with 35% bonus on miles flown, domestic lounge access, extra luggage.

As for Aeroplan 2020, nobody knows what's going to happen.

Since I fly premium economy with both airlines TPAC-wise, I get a decent seat and Zone 2 boarding with both. The only real thing that might be of *some* use is the lounge access, but I often just stay an extra few hours in Taipei and head to the MRT just in time for the flight.

No matter what, though, BR is much cheaper than AC, offers the red-eye flight from YYZ (0145) which I love, and short connection times in TPE. If I flew on AC, I'd sort of lose a day, and have to pay for a separate ticket as AC codeshares are at lol-silly prices.