As I have stated elsewhere, Port Dinllaen’s WTT is based on Holyhead. From there, the major changes are –
- The addition of a different route to Cardiff via Pwhelli. This adds a need to schedule “through trains” where Holyhead only had one line in and out.
- After Caernarvon, the route to Birmingham and ultimately London diverges over the Great Central (Ireland extension) – this means that a denser traffic route (supported by 3 position semaphores) would exist from PD to Caernarvon which means that the “relief” hidden pattern of trains that ran ahead (Down) or behind (Up) will appear as “R” (if required).
- There is a difference in pattern for mail/parcels traffic. These will become explicit services as we have shorter platforms at PD and so taking two coach slots on the express would cause too large a distruption. Traffic both to/from London and to/from Cardiff will have explicit services that include Royal Mail services (Night Mail and Day Mail).
Doing discovery of the Holyhead WTT is greatly assisted by AI. Rather than have it guess, I have uploaded spreadsheet files of the timetable as the raw material for asking questions. In my experience, Claude seems less likely to hallucinate services that don’t exist.
