The Steam Packet will try berthing the Ben-my-Chree in North Wales tonight as it explores 'back-up' options to secure sea services.
The company says it wants to assess Holyhead Port's suitability as an alternative to Heysham and Birkenhead whilst issues at other harbours are resolved.
It follows a number of incidents where the vessel hasn't been able to get into Heysham because of tides or debris - the company says Birkenhead isn't available permanently on a "suitable basis".
The port of Holyhead is three and a half hours sailing from the Isle of Man - passengers will not be affected by the detour as the trial is taking place during a routine maintenance night.
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