Hello does anyone know if you can change a train departure to earlier if you have a pre purchased ticket on Trentalia? We have a trip.planned to Bologna tomorrow morning from Rome
It depends on your ticket class or fare class. If you have an discounted ticket it generally is no change. If you have a base ticket, then you can change by going to a ticket window. You cannot just jump on a train (unless it is a Regionale) since all trains except the Regionale require a seat reservation.
Generally speaking, yes you can.
https://www.trenitalia.com/en/purchase/manage_your_ticket.html
Key phrase there being "According to the fare you bought..."