They have started limiting standbys on those Econo/Tango/Fun fares. However, you could pay $40USD per person on day of departure and have it confirmed right away (this started on 01JUN). Not bad if you want to spend the day in Toronto.
But, given that this is a US station not handled by AC's own staff, you might be able to talk them into letting you standby since they're usually not as strict as AC's main stations.