The Colchester was transferred to Holyhead from Harwich in 1972. Traffic on the new lift-on lift-off service was booming and in 1973 the services to Dublin and Belfast carried 73,000 containers.
The arrival of the ship, known affctionately as the long slim Panetella, brought the end of the old Slieve Bawn which was sold for scrap.
In 1974 the Colchester was tried on the Heysham - Belfast service, but this was short lived and she returned to Holyhead for lay-up pending sale. She was eventually sold for further service, leaving Holyhead for the Mediterranean in 1975.