canadian departures in 1930s

[nataliew]

Am hoping you can confirm my thinking...
an ancestor of mine emigrated to canada - there is a record of her and her family departing England and disembarking at Quebec destined for Toronto in 1911.
Through b m and d of children it's then possible to trace her and hubby in Toronto throughout the 1920s.
I've recently found a record which I believe is her travelling back to visit England - Florence Piper (married name) aged 56 (correct age) docking in London 12/8/1934 - she is a UK citizen but resident in a foreign country.
My question is that she embarks at Montreal - would this be a usual point of departure for Toronto residents in the 1930s? My understanding is that the St Lawrence Seaway wasn't built until the 50s so ocean-goers wouldn't be able to travel that far into Canada but I'd love it if someone could confirm!
Thanks

[BeeJay]

Yes, Montreal would have been the usual and nearest point of departure for her from a Canadian port, and she would likely have travelled there by train.

In the incoming passenger lists for 1934 about two-thirds of the ships arrived at Montreal and/or Quebec, the rest arrived at Vancouver, Victoria, Halifax and St. John NB.