Clydelink Ltd, which operates between Gourock and Kilcreggan, was late in applying for the annual licence to the Maritime and Coastguard Agency.

This meant that the Island Princess had to make a double trip for workers travelling to Faslane and Coulport on Thursday morning.

Chiefs at Strathclyde Partnership for Transport (SPT) — which subsidises the route to the tune of £200,000 — are said to be furious.

Councillor David Wilson, Inverclyde’s representative on the SPT board, said: “There has been a delay in getting that certificate.

“The Martime and Coastguard Agency were not satisfied, and on Thursday they had to operate with 12 passengers.

“There were 23 guys there for the 6.45am sailing from Gourock to Kilcreggan and 12 were taken over and they came back again for the other 11. I don’t think it’s good enough and I have great sympathy for these guys who are trying to get to their work.

“Officers from SPT will be looking closely at the situation — I would hope in future the owner would make sure he puts his boat to the MCA in time to get his certificate.” Clydelink Ltd is halfway through a five-year contract for the crossing.

Gourock councillor Chris McEleny today said he is writing to the company and SPT about the situation.

He said: “This is just the latest shambles under this operator.

“Since the current operator took over a few years ago cancellations are at a record high. Safety of passengers absolutely must be paramount but with the volume of sailings cancelled it is clear that the ferry is not fit for purpose.

“I occasionally use the service myself so I’m well aware of the concerns users have.

“Some face the prospect of having to regularly lose pay because they can’t make work, or they take holidays to cover their time off or have to fork out a fortune in petrol to drive to the other side of the water – they should be compensated.

“Unfortunately communication to passengers from the company is poor.

“It’s thanks to the staff on the ferry that people get updates by them personally in their own time.

“I’ve heard that in the past people who’ve complained to the company have faced being barred from the service so I hope the company will engage constructively with me when I write to them and SPT for a better understanding of the situation. “ A spokeswoman for the MCA told the Telegraph: “The vessel Island Princess held a class V Passenger Certificate valid until 11 March, 2015.

“Following routine practice the vessel is currently being surveyed.” A spokeswoman for the company contacted the Telegraph yesterday and said the ferry now had its passenger certificate.

Councillor Wilson also confirmed this and the service was operating as normal again as of 10am yesterday.