Mark IV Maintenance

[maitias]

I saw a number of weeks ago that the new Mark IV are going to have to be serviced to stop the carriages from swaying.

Being a frequent traveller on the Dublin-Cork-Dublin route Im wondering why it took them so long to decide to rectify this defect since they were on trail for over a year. Seems a bit obscured that this was not corrected when they were testing the trains. Does this also mean that they will attempt to reduce the noise when the train crosses over the points.

Does anyone know if this means that their will be an impact to the Dublin-Cork route in relation to services/timetable amendments? Will the good old reliable Mark III carriages be making a comeback to help shore up the shortfall in carriages available if such a scenario exists?