Can luggage be shipped ahead to the next destination hotel so one can travel light on the train? maybe just sending items in a large package from a post office near the hotel in Milan. Thanks. I will be there in October 4
There are many, for example Zyppy By DHL, TNT (I think now part of FedEx), UPS
http://en.zyppy.it
https://www.tnt.com/express/en_gc/site/home.html
TNT also has a partnership with Trenitalia which would give you a hefty discount if booked as part of a train travel with Trenitalia
https://www.trenitalia.com/en/services/luggage_transportservices.html
Delivery is within 24-48 hours.