I searched and could not find a response on this point in this forum. I also watched the Air Canada youtube videos about connecting through YYZ, though they did not answer my question. What's confusing me is that I see there is a U.S. Customs entry of some sort available at YYZ (such that the YYZ-US bound leg is treated as domestic US).

Does anyone know if, when arriving at YYZ from an international destination, connecting through YYZ to a US final destination (all on AC metal), we need to pick up our bags at YYZ and re-check them for the final US-bound leg? One of those traveling with us is mobility-challenged, so I want to make sure I have arrangements in place (as well leave enough time between connections) in case we need to move heavy bags around the airport. All travelers are U.S. citizens, in case that matters.

Thanks!