Thanks for the replies, all. I'll post the DP once I use it later this month.
Are you sure the upgrade is only good on regional? Acela business->first is a better value (and a bigger jump in service and comfort).
Yes, from the email: "Because we value your membership in the Amtrak Guest RewardsŪ program, we're offering you the chance to experience Business class on Northeast RegionalSM when you redeem your complimentary upgrade by April 7, 2017."
Fine print specifically calls out NE Regional and business class upgrade again, so no Acela for me.
