“I spent more of my life in the U.K. than in France,” Bertinet, 53, told NBC News, as he took a break from teaching a baking class at his cooking school in the picturesque city of Bath in southwest England where he lives with his British wife and three children.

“To have to prove 31 years of your life here? It’s a joke,” he said. “They can go to my Wikipedia page and see who I am.”

Frustrated, he shared his ordeal on Instagram, where it went viral.

Bertinet appealed the decision and can now stay in the U.K. indefinitely.

But he said he was worried about more vulnerable people — the elderly, those with fewer resources, insufficient language skills or simply confused about the application process.

“If this happened to me, it will happen to other people,” Bertinet said.

‘Proudest non-British British person’

The U.K. voted to leave the E.U. in a June 2016 referendum that revealed deep divisions in British society. Those in favor of leaving wanted to “take back control” of the country’s laws and borders. Immigration emerged as one of the major issues for voters.

As things stand, British citizens have the freedom to move and work across the entire bloc of other 27 nations that make up the E.U., while citizens from those countries enjoy the same rights in the U.K.

Removing Britain from this system and creating new immigration rules was a major motivation for many Brexit supporters.

In the lead up to the referendum, pro-Brexit politicians promised E.U. citizens already living in the U.K. that they would automatically be granted the right to remain in the country and that their rights would stay the same.

But those who now have to apply for the right to stay in the country say that promise has been broken.

“I really can’t get over the fact that I am made to apply to stay in my own home,” said Corinne Byron, 47.

Born in Belgium and raised in Switzerland, Byron moved to the U.K. in 2004 after marrying a British soldier.

“I was a rather proud army wife, as I even sang with the military wives choirs,” she said. “I guess you could say that I was the proudest non-British British person you could imagine.”

Uncertain about how she would be affected, Byron decided to apply for settled status for the sake of her British-born daughter.

But she said she felt “no joy whatsoever” when she got it.

“I felt humiliated that I had to apply in the first place,” she said.

Byron added that she was also concerned that future British governments could void the settled status system unless it was enshrined in law, putting her future in jeopardy.

Legal experts told NBC News that the rights of E.U. citizens are not in fact protected by adequate legislation backed by Parliament under the settlement scheme.

The scheme falls under the rules laid out in the U.K.’s immigration law.

These rules can be easily changed, whereas an act passed by Parliament, for example, requires much more scrutiny.

Prime Minister Boris Johnson also appears to be toughening his stance.

In his first speech after taking the job in July, Johnson assured E.U. nationals living in the U.K. that they will have “the absolute certainty of the rights to live and remain” in the country.

But shortly afterward, his official spokesman made it clear that this was not a promise of new legislation.

Ahead of his resounding win in the Dec. 12 election, Johnson said E.U. citizens have been able to “treat the U.K. as thought it’s part of their own country” for too long.

His remarks prompted a group lobbying for E.U. citizens’ rights to write a letter to the PM demanding an apology.

“Boris Johnson says we are welcome here, but anything that comes out of his mouth, you can’t trust,” Byron said.

‘Brexit or no Brexit, it doesn’t matter’

Przemysław Piechura, 38, left his native Poland seven years ago.

“For me, Brexit or no Brexit, it doesn’t matter,” he said, between washing vehicles at a car wash in west London, where he works. “Some people are really scared. And for what? This is no problem, Brexit or not. If there is Brexit, go home.”

Piechura said he was applying for settled status in the U.K., but he was thinking about returning to Poland because the economy there has been growing in recent years.

Przemys?aw Piechura, 38, has lived in the U.K. for 7 years. He is considering going home to his native Poland when Brexit happens. Yuliya Talmazan / NBC News

A Romanian co-worker, Cosmin Narcis Savu, 44, said he was also considering leaving after eight years in the U.K. and moving to Spain or Germany — both E.U. members.

With so many people in the Romanian expat community ready to leave, he said the U.K. government is making a big mistake.

“They are totally wrong on this,” he added. “After Brexit, half of small businesses will close straight away. Believe me, for Romanian people, it’s much better to leave.”

“Take this car wash, for example,” he said, pointing to the parking lot, where Piechura was readying to serve another customer. “What English person will work here? I have never seen a single English person work here in my life.”