My husband and I are arriving in Port of Spain on a Sunday evening (after 5 pm) and would like to take the 6:30 am ferry on Monday morning to Tobago. I read that you can purchase tickets in advance, but only in person at specific travel agencies. We have considered purchasing tickets on the morning of but read that the office doesn't open until after 7:30 am. Is it possible to purchase tickets the same day around 5:00 am? Or do we need to get to a travel agent on Sunday evening to buy tickets?