The Steam Packet Company has made changes to its timetable for the upcoming days.
The company says it's because of increased silting in Heysham.
The Manannan will now operate two sailings tomorrow in place of the Ben-my-Chree, setting off for Heysham at 8.45am, and returning at 2.15pm.
Meanwhile tonight's voyage to Heysham will now leave an hour later than originally scheduled.
Ben-my-Chree sailings from 7.45pm tomorrow until 2.15am on Friday have all been brought forward, apart from the 7.45pm crossing on Thursday.
The Steam Packet says all of the changes are necessary in order to work around water depths available.
Full details of the changes can be found on the Steam Packet's website.