Carriage displays and seat reservations reversed on splitting train (03/07)

rhizomergence · 7 Jul 2026

I travelled on 11:48 Paddington to Carmarthen on 3rd July. The service was formed as a 10 coach train, with 5 cars terminating at Swansea and another 5 going onward to Carmarthen.

When I boarded (holding a seat reservation for coach H), it was the second carriage from the front. The onboard announcements said the front coach calls at stations beyond Swansea, and the LCD displays indeed showed H both in and outside the train. Everything on the train including the seat reservation displays assured me that my seat was going to Carmarthen.

I fell asleep around 40 min after departure and when I woke up, I was surprised to find that the carriage I was now showing as Coach B, I was sitting in someone else’s reserved seat to Newport, and announcements were now saying that the rear 5 carriages were going to Carmarthen!

It made for a lot of disputes about seats and confusion overall. And since you can’t walk between the two 5-car sets, it made for a jog along the platform at an intermediate station.

Any idea what happened here? A set re-allocated during the journey or just wrong labels at the start?

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Crithylum · 8 Jul 2026

Wrong labels at the start. The train pulls into Swansea and only the rear 5 carriages reverse out to Carmarthen

800301 · 8 Jul 2026

rhizomergence said:
I travelled on 11:48 Paddington to Carmarthen on 3rd July. The service was formed as a 10 coach train, with 5 cars terminating at Swansea and another 5 going onward to Carmarthen.

When I boarded (holding a seat reservation for coach H), it was the second carriage from the front. The onboard announcements said the front coach calls at stations beyond Swansea, and the LCD displays indeed showed H both in and outside the train. Everything on the train including the seat reservation displays assured me that my seat was going to Carmarthen.

I fell asleep around 40 min after departure and when I woke up, I was surprised to find that the carriage I was now showing as Coach B, I was sitting in someone else’s reserved seat to Newport, and announcements were now saying that the rear 5 carriages were going to Carmarthen!

It made for a lot of disputes about seats and confusion overall. And since you can’t walk between the two 5-car sets, it made for a jog along the platform at an intermediate station.

Any idea what happened here? A set re-allocated during the journey or just wrong labels at the start?

If the headcode has been entered at the London end cab this can happen if the formation on the TMS has not been checked, Coach A should always be the Bristol end set.

It seems formation was not checked when the headcode was inputted in this case and either the TM/Driver has changed it on route

DelW · 8 Jul 2026

I travelled from Carmarthen to Reading a month or so ago. Leaving Carmarthen I was sitting in coach D, after Swansea I was in coach K, then after about Bristol, I was back in coach D again - all without leaving my seat.

WolvertonWorks · 8 Jul 2026

We travelled from Shrewsbury to Aberystwyth on 23rd June on a TfW service that splits at Machynlleth with one portion of the train going to Aberystwyth and the other to Pwllheli.

The displays at Shrewsbury station said the front two carriages - of a four car train - were for Aberystwyth, the rear for Pwllheli.

We and others duly sat in the correct portion of the train. The onboard screens showed us as being in the correct place for Aberystwyth.

Shortly after departure the train manager, who was a lovely helpful lady who clearly loved her job, announced that today the front portion wasn't going to Aberystwyth it was going to Pwllheli and vice versa! A few people heard her and started moving - some not easily as they had large suitcases they weren't expecting to have to drag through the train.

As she made her way through checking tickets she was telling everyone whether they were in the correct portion and more and more people started moving. Once she's made her way through all the train we saw her helping some people who needed help to move. She did TfW proud I felt.

We decided to wait until just before Machynlleth, on the assumption that some people would be alighting there and there might be more choice of seats, before moving as it was a constant flow of people moving ends until then.

rhizomergence · 8 Jul 2026

Your TfW experience sounds a lot better than my experience(s) with GWR.

Surely carriage numbering NEEDS to be clear for a splitting service. I’m lucky enough to be able to move myself and all my stuff through the train and then along the platform to a different set at short notice. I’m sure not everyone is.

As an aside I’ve travelled with GWR a total of six times, with a seat reservation every time, and only one of those times the seat reservation worked incident free! Most times the displays were not working or the train was short formed or something.

LittleRedTrain · 9 Jul 2026

WolvertonWorks said:
Shortly after departure the train manager, who was a lovely helpful lady who clearly loved her job, announced that today the front portion wasn't going to Aberystwyth it was going to Pwllheli and vice versa! A few people heard her and started moving - some not easily as they had large suitcases they weren't expecting to have to drag through the train.

Despite many trips on the Cambrian over the last 20 years, I can't say I've ever encountered the split happening this way round, so it's not surprising that the information systems weren't able to handle it.
Can the PIS on a 158 even handle multiple destinations anyway? I'm sure it normally shows a destination of Aberystwyth in all coaches until the split actually takes place anyway.

The TfW staff on the Cambrian really are excellent at making sure everyone is where they should be, on a service with a reversal and a split, it's not really surprising that people get confused. Their friendly and proactive attitude is often a breath of fresh air compared to some other TOCs.

WolvertonWorks · 9 Jul 2026

LittleRedTrain said:
Despite many trips on the Cambrian over the last 20 years, I can't say I've ever encountered the split happening this way round, so it's not surprising that the information systems weren't able to handle it.
Can the PIS on a 158 even handle multiple destinations anyway? I'm sure it normally shows a destination of Aberystwyth in all coaches until the split actually takes place anyway.

The TfW staff on the Cambrian really are excellent at making sure everyone is where they should be, on a service with a reversal and a split, it's not really surprising that people get confused. Their friendly and proactive attitude is often a breath of fresh air compared to some other TOCs.

You could be correct that the destination was showing as Aberystwyth in both portions of the train - I didn't look when we'd moved to the was-what-rear section before we set off after the split.

When we asked the staff member why this was happening she said she'd been told something like "the particular unit which had been going to Pwllheli needed to go to Aberystwyth for some reason". Is there a maintenance depot there, maybe as its the end of the line?

zwk500 · 9 Jul 2026

WolvertonWorks said:
When we asked the staff member why this was happening she said she'd been told something like "the particular unit which had been going to Pwllheli needed to go to Aberystwyth for some reason". Is there a maintenance depot there, maybe as its the end of the line?

I don't think there's any maintenance facilities, there's a small shed at Machynlleth. However, the distance from Dovey Jn to Aberystwyth and back is a lot shorter than to/from Pwllheli, so maybe the units needed to swap to avoid running out of miles/hours/fuel before their next exam?

lowe1409 · 10 Jul 2026

zwk500 said:
I don't think there's any maintenance facilities, there's a small shed at Machynlleth. However, the distance from Dovey Jn to Aberystwyth and back is a lot shorter than to/from Pwllheli, so maybe the units needed to swap to avoid running out of miles/hours/fuel before their next exam?

Could also be that if one unit has a fault it can still run with (I.e something such as a broken toilet or A/C fault), that one diagram is the diagram which ends in the depot for the night versus the other which just gets stabled somewhere

brad465 · 10 Jul 2026

There was a XC service I got from Bristol Parkway-Taunton earlier this year, where the 8-car Voyager detached a unit at Bristol TM, but announcements at Parkway wrongly said the rear unit would carry on, even though this was not possible without a stupidly unnecessary shunt. I boarded the front unit, with the staff member in the carriage confirming my suspicions, but it did mean several passengers changed units at Temple Meads.

1955LR · 10 Jul 2026

WolvertonWorks said:
We travelled from Shrewsbury to Aberystwyth on 23rd June on a TfW service that splits at Machynlleth with one portion of the train going to Aberystwyth and the other to Pwllheli.

The displays at Shrewsbury station said the front two carriages - of a four car train - were for Aberystwyth, the rear for Pwllheli.

We and others duly sat in the correct portion of the train. The onboard screens showed us as being in the correct place for Aberystwyth.

Shortly after departure the train manager, who was a lovely helpful lady who clearly loved her job, announced that today the front portion wasn't going to Aberystwyth it was going to Pwllheli and vice versa! A few people heard her and started moving - some not easily as they had large suitcases they weren't expecting to have to drag through the train.

As she made her way through checking tickets she was telling everyone whether they were in the correct portion and more and more people started moving. Once she's made her way through all the train we saw her helping some people who needed help to move. She did TfW proud I felt.

We decided to wait until just before Machynlleth, on the assumption that some people would be alighting there and there might be more choice of seats, before moving as it was a constant flow of people moving ends until then.

I have had this happen on two or tree occasions in the last 17 years and now double check when I get on that I am in the correct carriage

Newbury · 10 Jul 2026

The issues with the Carmarthen sets being the wrong way around are rather common, I’ve done Paddington-Carmarthen four times (two return trips) and have never had my seat reservation in the correct half.

rhizomergence · 10 Jul 2026

Newbury said:
The issues with the Carmarthen sets being the wrong way around are rather common, I’ve done Paddington-Carmarthen four times (two return trips) and have never had my seat reservation in the correct half.

That’s really quite a poor attitude toward customer satisfaction.

No wonder there are so many shorts/reels/tiktoks expressing confusion about trains splitting.

Belperpete · 13 Jul 2026

WolvertonWorks said:
You could be correct that the destination was showing as Aberystwyth in both portions of the train - I didn't look when we'd moved to the was-what-rear section before we set off after the split.

When we asked the staff member why this was happening she said she'd been told something like "the particular unit which had been going to Pwllheli needed to go to Aberystwyth for some reason". Is there a maintenance depot there, maybe as its the end of the line?

The destination displays always show Aberystwyth in both portions until the train divides at Machynlleth - and occasionally even after! The displays in 158s don't seem to be able to handle dividing trains - we await to see how the 197s will do.

While it is usual for the front unit to go to Aber, and the rear to Pwllheli, it does sometimes change. Sometimes it is the other way around, sometimes both units go to Aber, sometimes the rear unit goes into the depot and a fresh unit goes to Pwllheli. The depot for the Cambrian 158s is at Mach, and the usual reason for changing things is if the rear unit doesn't have sufficient fuel for the considerably longer trip to Pwllheli and back.

Sometimes, having got everybody in the correct units, the plan changes en-route to Mach.. But invariably the on-train staff and platform staff are good at keeping you updated, and will usually walk through both portions of the train at Mach to check that people are on the right train.

Even so, people do still manage to be on the wrong train. A week or so ago, someone with headphones in and totally oblivious to all that was going on around them managed to get themselves on the wrong train. Fortunately they realised before Dovey Junction, and they held the other train there for the passenger to be swapped over.

callumwright1 · 13 Jul 2026

It sounds like the two 5-car units were identified incorrectly when the train was prepared. The reservation system and coach lettering are loaded electronically, so if the units were coupled in the opposite order to what was expected, the coach letters and reservation displays can end up being wrong until they're corrected. Once the crew realised, they probably updated the train's configuration, which would explain why your coach suddenly changed from H to B and why the announcements switched which half was for Carmarthen. Unfortunately, because the units aren't connected internally, it leaves passengers having to move at the next stop. It's not common, but it does happen occasionally when units are swapped or marshalled differently before departure.

aar0 · 13 Jul 2026

Newbury said:
The issues with the Carmarthen sets being the wrong way around are rather common, I’ve done Paddington-Carmarthen four times (two return trips) and have never had my seat reservation in the correct half.

Even when the coach letters are correct, the auto announcements will insist the front 5 will carry on to Carmarthen, and the rear stay in Swansea. I flagged this to the guard once and he explained the front 5 would head to Carmarthen - it just happened they were the rear 5 from London… I didn’t find that very convincing.

Bikeman78 · 13 Jul 2026

Newbury said:
The issues with the Carmarthen sets being the wrong way around are rather common, I’ve done Paddington-Carmarthen four times (two return trips) and have never had my seat reservation in the correct half.

Agreed. The automated announcements and the guard often disagree. It is not possible to walk from one unit to another. So I don't see the point in mentioning it on board until after departure from Neath. There will be plenty of time to switch units whilst the train reverses and splits. The last thing we need is people rushing to switch units at the other stations en route.

Carriage displays and seat reservations reversed on splitting train (03/07)

rhizomergence

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Crithylum

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800301

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DelW

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WolvertonWorks

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rhizomergence

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LittleRedTrain

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zwk500

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lowe1409

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brad465

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1955LR

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