The harbour that was supposed to be used by two ferries being built at the Ferguson Marine shipyard may not be ready for them, even though they are more than six years late.

One of the first signs of the trouble that was to come over two ferries being built on the Clyde was the infamous decision to launch the Glen Sannox with painted-on windows in November 2017. Since then, more than six years have passed and work continues on the vessel and its sister ship, the Glen Rosa, at Scottish Government-owned Ferguson Marine.

In fact, so much time has passed that there could be further delays and cost increases – the current estimate for the two ships is more than £360 million – because the warranties on equipment installed on the ferries have expired. However, despite all this, when Sannox is finally finished – it’s apparently due to start sailing later this year – and when Rosa joins it, hopefully sometime next year, there may still be a problem.

For, despite the long passage of time, it appears that the harbour they are supposed to use at Ardrossan may not actually be ready. You may wish to read that sentence again, but yes, it’s true. They may have had many more years than expected to prepare but the harbour is not able to accommodate the vessels and may not be until 2026.

This would mean these two ferries, newly born but already elderly, would have to sail to Troon instead, some 15 miles down the coast. The practical consequence of this is that sailing times would be longer and, as a result, the number of sailings to Arran may have to be cut from five to four a day.

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