Easiest way is wait until you get to England. Any booking office can do them. Reservations are recommended but not compulsory. Trains will be busy on this date. LNER the operator on the route keeps one carriage reservation free and trains are frequent. 

No problem - LNER reservations are online and free. You can even choose alternative seats if the offered ones don’t suit.

https://www.lner.co.uk/travel-information/make-a-reservation/

Take a printout if possible.

Interrail reservations tool is far from universal on its access to any operators trains

The only problem with the LNER policy is that many travel without reservations so there is a real bunfight for those seats. They will probably be full before reaching later stations Most of the rest on busy trains will be reserved for part if not all the journey, so if you sit in one of those you may well be ejected and then stand for the rest of the journey.

You can still make reservations up to 5 mins before departure at main stations, but obviously a bit fraught if things are that close. They do close doors a couple of minutes before departure time and they are normally 9 carriage trains so a long way up the platform to carriage A or K depending on which end of the train is first class (Carriage K).

Tickets and reservations for that date are not currently available for booking.

https://www.lner.co.uk/travel-information/travelling-later/tickets-for-future-dates/

The period between christmas and new year is always used in the UK for wide scale disruptive engineering works and this year is no different, there are works planned for the main (LNER)route and the slower (Avanti) route between London and Scotland on those days.

The current times that some planners show is the base timetable not accounting for the disruption, you will have to wait until they finalise the corrected timetable and open bookings before being able to see what services are running.

You can set up an alert on the link above that will notify you when those trains are available to book.

I thought SNCF were the only ones closing doors more than a minute before the published departure time. Have others started to copy that passenger-hostile behaviour?

Since the UK started fining companies for poor performance there has been a noticeable change on the way departures are managed to avoid any delay on departure. Doors are closed promptly and the trains often depart a few seconds before scheduled departure time. 

On major stations the platform manager sends a request to signals that they are ready for departure and awaits the green light, Then up to 2 mins before departure the train manager closes the main doors and gets back on the train and, after checking the platform for clearance down the train, closes his door and signals the driver. 

So technically I suppose the last door is closed 1 min before departure. 

But I never expect to catch any train in the UK, or any other country for that matter, within the last 2 minutes by my watch.

I don't either, but that doesn’t make closing doors early (before published departure time) passenger-friendly. For a passenger, a train has departed when they can't board anymore. So all that matters to a passenger is until when a train can be boarded. If the operator wants to close the doors earlier, then they should publish an earlier departure time. Some authorities even require the doors to be open until the published departure time, e.g. in Switzerland but also in some of the Dutch regional concessions.

But I digress, this is an entirely different discussion :)

Thanks for the information.

Greetings!

I was looking to get a train to Edinburgh (and back to London from there) for next month, but it says that’s unavailable as well. Does anyone know if the platform has some error or the coaches are full and unable to get any seats? Because by doing a reserve from other sites, takes a lot of money and losing my Eurail pass on this trip is not good at all.

I appreciate all the help and support you can provide me!

p.s: I’m absolutely a newbie on this. It’s my very first travel outside my country :(

The free seat reservations are available on LNER website (the company running the train), here https://www.lner.co.uk/travel-information/make-a-reservation/

For other journeys in the UK you can use GWR website. Please note that reservations are not mandatory in the UK but recommended on some line : for example Edinburgh - London.

They are free at all times in the UK (except for sleeper trains).

How many times do Eurail/Interrail need telling that almost all trains in the UK have NO or OPTIONAL reservations.

This problem will remain, I'm afraid, until LNER (and a few others) stop sending incorrect timetable information.

Surely there is a role for EUR/IR to vet the info from any provider when they get feedback from users - LNER are clear on the website that reservations are highly recommended but there is one coach left free on all trains.

It is clear that many users are being given misleading info and, whilst accepting that there are many operators and dynamic info coming in at all times, surely Ir can at least correct these blatant faults once identified.

Well, it seems I have my booking reservation in the LNER website done. Got my confirmation and the seats reserved. Now, I just need to place the booking reference into the Eurail Planner App and show the ticket (QR code) when I board the train?

I really appreciate all your help, and yes, the information is quite misleading when it comes to this.

Reservations can't be added to the app. In the app, you just need to add the train you use to your pass, so you can generate a QR code.

The e-mail from LNER with your seats is all you need and then only to find your seat (and eject any squatters).