Some of these were covered in other threads dealing with major service changes, but here they are in a nutshell:
System timetable - April 2017
Northeast Corridor: New York-Washington - April 3, 2017
Northeast Corridor: Boston/Springfield-Washington - April 3, 2017
Northeast Corridor: Virginia service - April 3, 2017
Pacific Surfliner - April 3, 2017
Vermonter/Ethan Allen Express - April 3, 2017
Empire Service - April 9, 2017
Maple Leaf - April 9, 2017
City of New Orleans/Illini/Saluki - April 1, 2017
Illinois/Missouri Services - April 1, 2017
Lake Shore Limited - April 8, 2017
Empire Builder - April 29, 2017