The Steam Packet says it's cancelled its Saturday afternoon sailing because of bad weather.
Manxman's 3pm crossing from Douglas to Liverpool will no longer be going ahead.
It means her return voyage to Douglas is also off, having been scheduled for 8pm that evening, Saturday, April 4.
Meanwhile three other sailings are also listed as being at risk that day, as is the overnight sailing from Heysham to Douglas on Sunday, April 5.
It comes as Storm Dave is expected to hit the Island on Saturday evening.
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