Originally Posted by octr202

Not all holiday extras are commuter equipment. IIRC usually those have 10XX series train numbers.

There are usually some 11xx series extras, which run with Amtrak equipment. They're just extra trains not usually scheduled.

Where are you booked to/from? The commuter equipment usually only operates NYP-WAS, not up to Boston. You said 6 hours, that should mean you're going past NYC and you should be OK.

Edit info - Looks like the holiday timetable lists the commuter train extras as "Holiday Extra" and they only run NYC-WAS. There are many "Northeast Regional Extras" which will be normal Amtrak equipment.