Ms Flint, who was shadow secretary for energy and climate change under Ed Miliband, resigned yesterday but waited 24 hours to make a public announcement out of ‘courtesy’ for Mr Corbyn, she said.
She is the latest in a growing number of shadow team members to quit following the election of the left-wing leader and follows Yvette Cooper, Tristram Hunt, Liz Kendall, Chuka Umunna, Rachel Reeves and Mary Creagh.
Leeds Central MP Hilary Benn remains in his position as shadow foreign secretary and Mr Corbyn today announced Hemsworth MP Jon Trickett has taken the role of Shadow Local Government Secretary and Wentworth and Dearne MP John Healey will be Shadow Housing Minister.
Mr Healey said: “Housing has long been a passion of Jeremy’s, so I’m pleased to have his backing to do this job at full shadow cabinet level. It shows the high political priority he gives to tackling the housing crisis.
Families across the country desperately need a government that will step up to the plate on housing, but this Conservative government has stepped back. As a Labour opposition it’s our urgent task to expose the way this government is letting people down, and to show the big difference a Labour government could make.”
In a statement Ms Flint said she felt she could best support the party from the backbenches and wanted to reach out to voters who had turned away from Labour.
She said: “I spoke to our Chief Whip Rosie Winterton. I informed her that, after careful consideration, I have decided I can best support the Labour Party and the leadership from outside the Shadow Cabinet.
“I remain loyal to the Labour Party and will do everything I can to help us win the next General Election in 2020.
“My first and foremost concern has always been serving my constituents in Don Valley, to which I will continue to devote the same energy as I have for the last 18 years.”
In a clear signal of the direction Mr Corbyn will take on economic policy, the new leader appointed fellow leftwinger John McDonnell as Shadow Chancellor.
Barnsley East MP, former Shadow Transport Secretary and Mr Burnham’s campaign manager Michael Dugher was reported to have been moved to the culture, media and sport brief while Angela Eagle was made Shadow Business Secretary and Diane Abbott Shadow International Development Secretary.
Two lesser known figures were also awarded shadow cabinet posts with Lewisham East MP Heidi Alexander becoming Shadow Health Secretary and Feltham and Heston MP Seema Malhotra was made Shadow Chief Secretary to the Treasury.
Manchester MP Lucy Powell, who played a leading role in Labour’s General Election campaign, was made Shadow Education Secretary.
Ms Creagh, the Wakefield MP who occupied the international development brief under Ed Miliband, and one-time leadership candidate Chuka Umunna stepped down in the aftermath of Mr Corbyn’s victory.
Both hinted that Mr Corbyn was set to adopt a more eurosceptic stance while they wanted the freedom to campaign for a ‘yes’ vote in the forthcoming EU referendum.
Leadership candidate Yvette Cooper and fellow Yorkshire MPs Rachel Reeves, Dan Jarvis and Angela Smith had already chosen to move to the backbenches.
In a statement, Ms Smith, who was Shadow Farming Minister, said the “depth of difference” between her and Mr Corbyn on issues such as NATO and the European Union made it “very difficult” to remain part of the frontbench team.
She said: “My decision is not one that has been made lightly. I enjoy my role as shadow Food and Farming Minister and my rural affairs brief is one which I consider to be critical to the future success of the party.”
But she added: “I cannot, however, continue in this role when I have such fundamental differences with the leader on key issues relating to defence and international relations.
“To serve on the front bench in such circumstances would be dishonest, serving nobody’s interests.”
The scale of the problems Mr Corbyn faces were underlined as Mr Benn declined to offer full endorsement for Mr McDonnell’s appointment as Shadow Chancellor.
Asked if he was 100% behind the move, Mr Benn told BBC Radio 4’s Today programme: “This is the choice that Jeremy has made. I respect the choice that Jeremy has made as leader.
“We have just come off the back of two bad election defeats for the Labour Party, and our principle task is to win the people’s trust when it comes to the economy.
“John’s first and last task as shadow chancellor will be to win the trust and confidence of the British people in arguing for a different economic policy.”
Barnsley Central MP Dan Jarvis, who declined to run for the leadership, said he had received “vitriolic messages” after saying he doubted he would be called on to serve on Mr Corbyn’s frontbench.
But he called on the leader to unite different factions to create a “broad church”.
Writing in the Telegraph, he said: “History does not have to repeat itself. And it is the responsibility of everyone in our party to ensure that it does not.
“That means putting aside differences and pulling together for the good of our party but, more importantly, for our country.
“Because a divided Labour party will be resoundingly rejected by the British people. Our new leader should use his mandate to reach out across the party, bringing people into the fold.”
Pressed on whether he welcomes Mr McDonnell taking charge of the Treasury brief, Mr Benn said: “I welcome everybody who is serving in Jeremy Corbyn’s cabinet... because Jeremy won a thumping victory, we have a responsibility to rally round him.”
He went on: “Jeremy has appointed people to his shadow cabinet who he knows have different views to him on some issues of policy.
“That is about a different kind of politics. One of the reasons I think he won such a large mandate was partly about policy for some people, but also because he represents something different.
“He is going to respect the different views that people have got, and we have got to respect each other. It will be for the shadow cabinet and then ultimately for the Labour Party to decide what our policy will be going forward.”
Mr Benn, the first senior member of the new-look front bench to appear on the airwaves, attempted to calm fears among many Labour MPs that Mr Corbyn could campaign for Britain to leave the EU in the in/out referendum expected next year.
Chuka Umunna stood down as shadow business secretary complaining the new leader had refused to give him an assurance he would not back a “Brexit” vote.
But Mr Benn said: “He wants to ensure that Europe in particular works better for working people.
“Jeremy said whatever differences we may have with some aspects of European policy and whatever reforms we want to see, we will stay to fight together for a better Europe.”
Mr Benn also dismissed concerns about the lack of women in the top posts - traditionally considered to be shadowing the chancellor, home secretary and foreign secretary.
“It all depends on your definition of top job,” he said. “That is a slightly old fashioned view. International development, Diane Abbott is going to be doing that. The refugee crisis has taught us how important it is to play our part in supporting people.
“Education of our children is vital, Lucy Powell is going to be doing that., And Angela Eagle, as well as being shadow business secretary, she is going to be the shadow first secretary of state.”
Chief Whip Rosie Winterton, the Doncaster Central MP, will continue in her post.
The Conservatives will seize an early opportunity to try and paint Labour under new leader Jeremy Corbyn as a party out of touch and in hock to the trade unions today as they push ahead with major reforms to strike laws.
Labour is expected to mount a strong attack on plans to tighten the rules on industrial action in the wake of the leftwinger’s overwhelming victory in the party leadership race at the weekend.
The Conservative Government will argue it is trying to protect ordinary people from unjustified disruption to services when the reforms are debated in the Commons today.
But Tory Haltemprice and Howden MP David Davis, the former Shadow Home Secretary, warned his party that it could inadvertently strengthen Mr Corbyn’s hand unless it approaches such issues with care.