No matter what time, date I look at to book London to Paris on Eurostar there is no availability. I am trying to book December 29th London To Paris with the Eurail pass and I get no tickets available. even when I use the https://www.b-europe.com/EN/Booking/Tickets site and look at different times and days even there are no tickets. Seems odd to me that it is so difficult to book seats for this route.
I know Eurail only has so many seat reservations for Eurostar but literally there are ZERO tickets.