We will be arriving on a cruise ship in Montreal around 8 am on a Sunday and our flight is not until 7pm. We would like to be able to spend some time seeing the city. In looking on the web, I found that there is a baggage storage facility at Central Station. However, the via rail website states "Baggage Service offered: Baggage room with baggage checkroom, with restrictions."

Does anyone know what the restrictions are? Any other convenient options?
Thank you