Here's a reminder of the key moments from this morning's historic ferry journey in the Firth of Clyde:

• The long-awaited Glen Sannox ferry has completed its first official passenger voyage from Troon to Brodick on the Isle of Arran and back
• The vessel's design and construction at the Scottish government-owned Ferguson Marine shipyard has been a huge source of controversy
• The ferry was delivered seven years late and millions of pounds over budget
• When combined with the cost of the unfinished Glen Rosa, its sister ferry, the cost rises above £400m
• That works out as around £200m for the Glen Sannox alone
• With a capacity for 127 cars and 852 passengers, Glen Sannox will help relieve pressures on the state-owned operator CalMac
• It has struggled in recent years to maintain services with ageing and increasingly unreliable vessels

That's all from our live page team. The editor was Paul McLaren, with Calum Watson live reporting from on board the Glen Sannox. The other writers were Craig Hutchison and Ashleigh Keenan-Bryce.

You can read more on our main story here.

This morning's conditions may have been a bit choppy but, generally, the reaction from passengers has been very positive.

And even the pets seemed to have enjoyed the trip.

Calum Watson
In Troon Harbour

Captain Tobias Sogl, one of the CalMac masters on today's crossing, tells me he was honoured to play a role in some of the ship’s first passenger sailings.

“We’re very confident in the vessel. It’s powerful and manoeuvrable.

"We’re still on a learning curve, finding out how it performs in different winds and sea states.

"You can’t expect it to happen at the click of a switch but it will definitely be a more resilient vessel."

With the new ship being too big to operate from Ardrossan, residents of the North Ayrshire town are worried about the future.

A plan to redevelop the privately-owned harbour has stalled over disagreements about funding.

"This harbour's been a great port for 200 years and it's just disintegrating," says Frances Gimour, chairwoman of Save Ardrossan Harbour campaign.

"The powers that be are allowing it to happen. When we try to get answers, they just blame each other."

Committee member Alison Montgomery says it would have a big economic impact if ferry services switched to Troon on a permanent basis. .

"We've got Ardrossan Castle, loads of tourists from all over the world stop in the town en-route to Arran. We'll lose that footfall and it's got a massive impact on the local businesses."

Fellow campaigner Christine Cowie says small businesses could be particularly badly hit.

"The bookstores, the dog groomers, the dentists - people from Arran use these places," she says.

• Future of Ardrossan harbour in limbo, says ferries boss

As we've been reporting, Glen Sannox has successfully berthed in its home port of Troon - but that wasn't always going to be the plan.

Ardrossan in North Ayrshire is the closest mainland harbour to Arran, offering the shortest crossing.

The business case for Glen Sannox and its sister ship Glen Rosa said they were meant to fit existing infrastructure.

But after taking advice from consultants, CMAL decided to widen the ships, while the equipment to allow it to run on liquefied natural gas (LNG) and other specifications meant they ended up being heavier than anticipated.

Ardrossan harbour is shallow and tricky to navigate, with a notorious handbrake turn required to berth.

After berthing simulations using computers in Glasgow, it was decided it would be too risky to operate such big ships from the port unless the facilities were redeveloped.

A plan to remodel the privately-owned harbour was signed off by then Transport Minister Humza Yousaf in 2018 - but two years ago it was paused by Transport Scotland after concern about rising costs and how much public money would be required for the project.

Last week the boss of CMAL said he believed talks to revive the plan were "in the middle of nowhere".

So, for the foreseeable future, Glen Sannox will operate from Troon, about 25 miles further down the coast.

It means a longer journey time - one hour and 15 minutes compared with 50 minutes from Ardrossan - and there will be three daily sailings, rather than five normally offered from the closer port.

Image source, Christopher Brindle

Back at the Ferguson shipyard in Port Glasgow, work is continuing on an identical ship to Glen Sannox.

Glen Rosa was launched last April and is currently moored beside the yard for fitting-out work.

The ship is currently due to be finished by the end of September but we'll get a new update on costs and delivery in about a fortnight's time. At the weekend, it was reported there could be six-month delay., external

A "lessons learned" assessment is taking place at the shipyard before the final push to get Glen Rosa into service.

• Glen Rosa successfully launched into the Clyde
• Could Glen Rosa be the Clyde's last traditional ship launch?

Image source, PA Media

The interim chief executive of Ferguson Marine, the Port Glasgow shipyard which built Glen Sannox, says it's a "real milestone" for the yard to see it carry its first passengers.

"We acknowledge that the process wasn’t without its challenges, however this vessel is the first in her class, a real Clyde-built industrial achievement, and a testament to the skill and dedication of all who had the privilege of working on her," John Petticrew says

Mr Petticrew, who took over as CEO last March, says the ship shows what the Ferguson yard is capable of.

"We are delighted that she is now in service and look forward to seeing her serve our important island communities for years to come," he adds

There’s a rumble from the side thrusters as the ship manoeuvres in Troon harbour.

Over the Tannoy comes the announcement that we’ve arrived and passengers can soon depart.

The numbers have chopped and changed so often, it's hard to keep track

The original contract for two ships was for £97m - and £83m of that was paid out before the Ferguson shipyard went bust again in 2019.

Then there's £45m of controversial government loans, very little of which was recovered.

After nationalisation in 2019 and the appointment of a "turnaround director" the cost to complete both ships was put at £110m,

That has since risen to about £150m per ship - so roughly £300m in total. There are a few other costs not included in that, like renewing equipment warranties.

Put all those sums together and we're definitely north of £400m, so we're looking at about £200m or more for Glen Sannox alone.

Calum Watson on board Glen Sannox

During the choppy crossing, a BBC iPhone that was recording the journey was feared lost overboard.

Fortunately it dropped into a lifeboat and the device has been recovered.

That seems to have been the only minor mishap and CalMac seems delighted with the way the ship has performed.

Weather-related cancellations are a scourge of island life, and there will be real hope this ship heralds a much more resilient ferry service in future.

Calum Watson on board Glen Sannox

The Ayrshire coast comes into view as Glen Sannox heads for Troon.

Image source, PA Media

Scotland's First Minister John Swinney spoke about the long delay in bringing Glen Sannox into service when he was interviewed on the BBC's Good Morning Scotland programme.

"These ferries should have been built a great deal faster than they were built and I apologise unreservedly to island communities for the delays in those two ferries," he said.

Swinney was also asked in last week;s interview if it was time for a shake-up of the "tripartite" arrangement - where responsibility for ferries is split between CMAL, CalMac and Transport Scotland - to avoid "Mexican standoff" situations where they blame each other for the problems.

He was non-committal on whether there would be changes, instead saying the important thing was to make sure islanders get the ferry services they require.

"I use the CalMac ferry network on a regular basis... and I have a huge amount of admiration for the work that goes on in that network to support our island communities," he said.

Read more here.

Calum Watson
BBC Scotland News

Glen Sannox is the second largest and the most complex vessel ever built for ferry operator Caledonian MacBrayne.

But six years late and four times over budget, the project has been hugely controversial.

So how did this story unfold and why was this ship so hard to build?

Read more here.

With its first day's sailings well under way, it's a good time to recap on the controversial saga of the Glen Sannox ferry and how we got to this point.

The contracts for Glen Sannox and a second vessel were awarded in 2015 to Ferguson's shipyard in Port Glasgow, just a year after the last commercial yard on the Clyde was rescued by businessman Jim McColl.

It was hoped the order for the two dual-fuel ships - capable of running on diesel and gas - heralded a revival for Clyde shipbuilding which once dominated the world.

But things soon turned sour as the build ran into trouble, with the yard's management and government-owned ferries agency Caledonian Maritime Assets Ltd (CMAL) blaming each other for the problems.

Without agreement on extra cost claims, the shipyard went bust again in 2019 and was nationalised - but difficulties building the ships continued with costs spiralling upwards.

Meanwhile, government-owned ferries operator CalMac has struggled to maintain lifeline services with an ageing fleet that are increasingly prone to breakdown.

Glen Sannox was finally delivered to CalMac in November, nearly seven years late and the cost of the two ships has risen above £400m, more than four times the original contract price.

Read more about the ferries saga here.

Linda Johnston is the co-founder of the Auchrannie Resort in Brodick and has lived on Arran for more than 30 years. She says the ferry disruption over the last few years has made things challenging for her business.

“Clearly people have been a bit put off coming to the island which makes it difficult financially for the business and the community," she says.

“But at the end of the day the islanders get through it and we are keen to look to the future. Our visitors are similar, they love coming to the island so they have made the effort to come along on the journey with us and we are looking forward to things being a bit easier in the future.”

She says she is hopeful the new ferry will help make the Arran service more reliable.

As Glen Sannox pulls away from Brodick on the Isle of Arran, we've been speaking to islanders to get their view on what its entry into service could mean forh tem.

Sheila Gilmore runs Visit Arran. She is hopeful that the new ferry service will help bring people back to the island.

She says people on the islands have to work together to "change the minds" of visitors and bring back people who stopped visiting because they felt they couldn't rely on the ferries.

The great ferries saga is far from overpublished at 09:12 Greenwich Mean Time 13 January

09:12 GMT 13 January

Glenn Campbell
BBC Scotland Political Editor

After years of delay, rising costs and ministerial frustration, today is about delivery for the Scottish government.

The Glen Sannox is in service and starting to take some of the strain off CalMac’s ageing and temperamental fleet.

That’s the good news, but getting this vessel to sea has not only cost the Scottish government financially, it has had a big reputational cost too.

For their political opponents, the ferries have come to symbolise anything and everything considered as underperformance or failure by the SNP administration.

Ministers remain vulnerable to circumstances. The performance of the Glen Sannox. The completion, delivery and operation of the Glen Rosa. Their wider efforts to upgrade the CalMac fleet.

Then there’s the future of the Ferguson shipyard. Trying to secure a viable future for it and finding a commercial buyer to take it out of public ownership. Easier said than done.

As the ship heads back to the mainland, business is brisk in the restaurant.

Over on the Arran side, the seas feel a lot calmer and the prospect of a good fry-up is perhaps more enticing than earlier this morning.