I travel NYC-DC regularly due to family in DC. I was looking at the train schedules over Passover week, 2023 (i.e. first week of April), and it looks like the last departure out of NYC to DC is now 11:11pm on Fridays (was 7:40pm for Regional and 8:13pm for Acela). Saturday service also runs until 11:05pm as well (used to end with the Vermonter at 7:01pm).
Friday service - increased from 33 trains/day to 40 southbound. Added an Acela at 9:05pm, Regionals at 9:10, 10:05, and 11:11pm. Also looks like a new early-morning regional at 5:15am!
Saturday service - increased from 22 trains/day to 27 southbound. Added Regionals at 8:01, 9:05, and 11:05pm.
This is something approaching a normal late-night/early morning schedule. I've seen this before on the site, but I think they're planning to actually do it this time around. Reason being is that this is NOT the pre-COVID schedule of 43 trains per day (visible if you look in 2024), and the late-night trains weren't listed until recently, so they actually added them back.
Good job, Amtrak! I was kind of assuming that late-night service in the Corridor was never coming back after the COVID-era staffing and service cuts. Now please bring back the Adirondack to Montréal!