Nautilus says changes would mean members spent 70-80 more days at sea
The union in dispute with the Steam Packet over terms for the ferry operator's officers says further discussions have taken place.
Nautilus is balloting its members over updates to workers' terms that would see crew required to live aboard.
The union estimates the changes would require staff to spend an additional 70 to 80 days per year away from their homes.
Senior National Organiser for Nautilus Garry Elliot says what the employer is offering isn't enough:
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