Translink were consulted, they had to provide the paths for the service and agree to the increase on Sunday.
Both IE and NIR management have been asked over and over again to get a train to Dublin before 0845, its a serious business need to do this. Equally the ask for a train to Belfast before 9am has been made numerous times (0610 would work fine...)
NIR its their problem to provide a connecting train
No amount of improvement would get the 0650 to Dublin for 0845, just not possible, non stop, nothing in the way 1 hour 43 is the current benchmark, add in 4 stops, you are over 2 hours
Its very obvious how much slower the train is once in Northern Ireland, its painfully slow, while Dublin Dundalk is always a fairly swift trip, basically an unbroken 90 mph railway north of Malahide bar the stations in Drogheda and Dundalk