from East of Swansea to Llanelli without stopping at Swansea.
There are actually at least two different routes that can be done, so even if you find a service that is scheduled to do that there's no guarantee it will use the Swansea District Line (SDL). I made use of the Fishguard daytime 'boat train' a number of times during the Arriva Trains Wales franchise, sometimes it did used the SDL, other trips used the avoiding line around the back of Landore depot instead (and thus travelling non-stop through Neath and Gowerton rather than Bynea and Llangennech). A shake up of the timetable by TfW since the 197s entered service has now eliminated most of the odd services that don't fit the standard pattern though I think, so I'd be quite surprised if there are any daytime passenger services avoiding Swansea by either route now.
No. Pretty sure that only HoWL trains do that, and so it's been for decades (ever?). If they introduced Port Talbot - Llangennech trains, even one a day, it might become a legal pain to drop them later - parliamentary service and all that legal stuff.
The only time I can think of when non-HOWL services
might have called at Bynea/Llangennech during Arriva's franchise is while the line through Gowerton was closed to replace the bridge and redouble the track (since HOWL services wouldn't have been able to take their normal route into Swansea). Even then, I'm not sure if they did call at all or just used replacement road transport and/or run the HOWL trains to Carmarthen (or terminated short at Llanelli) instead of Swansea.
The handy lunchtime Fishguard rare track extravaganza (which also did the avoider at Carmarthen on the way out) ceased when the Swanline was rewritten (December last year?)
For quite a while, there were
two daytime passenger services using the Carmarthen avoider - both westbound and both headed for Fishguard! The 09:40ish arrival in Fishguard (which I think came from Swansea off a Heart Of Wales working) and the lunchtime 'boat train'. Not sure if there's any booked passenger work on the Carmarthen avoider anymore.
Presumably the class 37 and class 50 hauled 'boat train' under Wales & West and early Arriva days (which sadly was either before I'd moved to Wales or before I got into the Welsh rail scene, so I never got to see it for myself) would have ommited Carmarthen in both directions? Or did they run-round in Carmarthen station - is the avoider even passed for passenger use eastbound (I'm aware of occasional railtours into Pembrokeshire, but even those seem to work top & tailed and go into Carmarthen in one direction to turn the train so the steam loco is at the front for more of the trip)?
I did try around 2021/22 catching the Fishguard from Llanelli to Port Talbot but unfortunately on the day it went via Landore. I assume the train crew didnt sign the SDL or there was some other reason. I think that quite often happens now.
Go far enough back in time and the Fishguard 'boat train' didn't stop at Port Talbot either. I'm pretty certain that, for quite some time, Arriva's timetable had it as 10:57 Cardiff Central to Fishguard Harbour, calling only at Llanelli and Whitland, then returning as the 13:30 from Fishguard Harbour to Cheltenham Spa with the only stops before Cardiff being Whitland, Carmarthen and Llanelli before picking up the normal Cheltenham stopper pattern from Cardiff Central. Non-stop between Cardiff and Llanelli both ways - would have been quite something if only the rolling stock had been decent (sadly it was normally booked for a 150, and I think I have a photo or video somewhere when either 150+Pacer combo or a pair of Pacers turned up, though I've no idea if that was as-booked).
Unrelated to Brexit - the boat train has been getting worse since the 1990s. Back in the early '90s there were 2 IC125s a day to London from Fishguard. That changed to loco hauled Cardiff only daytime, but the overnighter was still a HST in around 1996. There hasn't been a HST on that service in decades.. just units with sometimes timing incompatible with the ferry
I'm fairly sure the overnight Arriva DMU from Fishguard to Swansea or Cardiff was still in the timetable (sometimes as a bus, possibly on Sundays?) when the extra trains to/from Fishguard were introduced in 2011. Unforuntely, Stena Line withdrew the Lynx (summer-only fast ferry) from Fishguard shortly before, so we never got to see a train service connecting with that; both year-round conventional sailings had rail connections in Fishguard in both directions though (as they did before) - not so much on the Irish side though maybe. Then, around the time of the UK's decision to leave the EU, Stena Line changed the long-standing ferry times. If I recall correctly, that change ultimately resulted in Fishguard losing a Mon-Sat train service (7 each way down to 6) - although I believe an oversight with the franchise spec meant ATW (or was it TfW by then?) were forced to keep running the 01:50 for a while even though the evening ferry was then connecting into the previous evening's last Fishguard to Swansea service instead. I think TfW's lastest timetable shakeup restored 7 trains each way to Fishguard but this was a long-absent mid-afternoon train and the evening/overnight ferry seems to miss the trains in Fishguard now (both ways). I think TfW are now advertising rail-sail tickets for the daytime sailing only in both directions.
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