Apologies - I think we may have been speaking at cross purposes – I thought you were referring to no through ticketing from this side (Ireland) hence my comments/questions.

The Irish Rail timetable is in National Rail Enquiries but doesn’t seem to be fully up to date e.g. showing a 17.55 ex Europort (now 18.00).

Either way it seems quite evident that there is resistance somewhere to through ticketing.