My family is flying into Milan and taking a train down to Florence the end of March and it appears I am able to book this train. However, due to some connecting flight issues on the way home, we are now taking a direct flight out of Paris so we need to get from Florence to Paris by train (which should be beautiful), but those tickets are not available yet. When should I expect to be able to purchase those tickets? Also, should I wait to purchase my tickets from Milan to Florence and how much time do you think I should allow from my flight arrival to my train departure at Milano Centrale? Thank you in advance.