A study which found the building of one of the delayed ferries at Ferguson Marine was not value for money is estimated to have cost more than £600,000.
Wellbeing Economy Secretary Neil Gray announced last month the Scottish Government would plough ahead with the building of the Glen Sannox and as-yet-unnamed hull 802 at Ferguson Marine, despite a study suggesting it would be cheaper to commission another vessel from a different yard than to build the latter ship.
Gray told MSPs that continuing the work would secure jobs at the beleaguered yard, which was saved from administration by the Scottish Government in 2019, and ensure both vessels enter service on routes to the islands earlier than commissioning a replacement for 802 elsewhere.