The Steam Packet Company says a technical issue was behind the Ben My Chree not being able to leave Heysham Port.
In a post, the company says the issue meant the anchor of the vessel, which had been used during berthing, couldn't be raised.
As a result, its 2.15am journey was unable to go ahead.
However, the tide has now dropped below a level where she could leave Heysham Port - meaning the boat is now en route to Douglas.
Manannan was drafted in at short notice to operate the 08:45 scheduled sailing from Douglas to Heysham.
Since, it's been announced the Manannan will also undertake this afternoon's voyage from Heysham to the Island.
Further, it's had a knock-on effect to other sailings - this afternoon's 3pm sailing to Liverpool will now set off at 4.45pm, and tonight's 7.15pm has been pushed back to 8.15pm.
The Steam Packet has apologised to those whose journeys have been disrupted and says its working to get sailings back on schedule as soon as possible.
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