We want to leave from Milan Central train station and go to Tirano to pick up the Bernina Express there. We've seen multiple references on the web to this being a 2.5 hour train ride to Tirano, but when I go to any sites (Trenitalia, Trenord, etc) all the routes are described as taking 3.5 hours and include a bus connection.
Is there any train-only way to get from Milan to Tirano?