I'm planning a trip to Italy in September. From what I've read, most suggest buying train tickets the day of or day before. However, when I'm looking online, for instance a ticket from Rome to La Spezia tomorrow starts at 54€, while tickets on the day we would be traveling in September are currently starting at 19€. Is this just because it is currently June and a high travel season? Or should we go ahead and book tickets now to lock in a lower price? Thanks so much!