Along with financial settlement and trade, the rights of citizens are a crucial part of the divorce talks between the UK and EU. But progress has been slower than many had hoped. In the meantime, anxiety grows among many of the three million EU citizens in the UK and 1.2 million Brits living and working in the EU. Chancellor Angela Merkel has sought to reassure the 100,000 Britons living in Germany that no one will be sent home, but with an election on the horizon, future conditions are anything but clear. Merkel's advice? Go for German nationality, as she told one British expat: "to put yourself on a completely safe track."

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In Germany, Brits have been scrambling to get citizenship, which they seem to see as an insurance policy, not only to be able to remain in the country but also to retain the broader palette of rights they enjoy as EU citizens. Germany's Statistics Office released figures in June revealing an "extraordinary increase" in the number of British citizens granted German passports in 2016. Overall naturalizations increased by 2.9 percent in comparison to 2015, whereas the number of Brits granted German citizenship soared by 361 percent to 2,865. While the agency does not specifically gather information on motivation to acquire citizenship, it did note that the surge was "quite obviously due to Brexit."

For those who are well settled in Germany, applying is an administrative burden, but the requirements are not especially onerous: Those who have lived in the country for eight years (seven, if they pass a German-language integration test) — or for three years and been married to a German for two — are eligible to apply. Other requirements include proof of language proficiency, financial independence, a clean criminal record and a fee of 255 euros ($304).

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For Duncan Ballantyne-Way, 36, an online art magazine editor who lives in Berlin with his German wife and children, such requirements were not much of an issue, but he doubts would have applied if it weren't for Brexit: "In the same way other Europeans living in UK had the option to apply for permanent residency or a passport before now, why go through the process if there's no need? Brexit is accelerating the process, because people want to be sure they are not cut off, that they don't close down their options without realizing it."

Time limit for dual citizenship

Nick Wolfe, 29, a lawyer in Munich, says his recent application is "purely pushed on by Brexit" as well as the tight timeframe: "If you want to take German citizenship, you have to renounce your previous one, unless you are an EU citizen. What the relevant authorities here have been saying is that if you actually receive your German citizenship before March 2019, you're okay. If you receive it afterwards, you will have to give up your British nationality to take up your German one."

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And if it came to it, Wolfe would find it hard to give up his British nationality: "There's a very emotional connection to it. So that's why it's obviously best if you can have both."

Indeed, time is running out to submit a citizenship application. The city of Munich received 271 in the first six months of this year and granted 88. But each local authority handles applications separately, and requirements and processing times can vary wildly. In some places applicants wait up nine months just for an initial appointment, a further few months for an appointment to submit their application and then six to 12 months for processing, taking the amount of time to receive citizenship beyond the March 2019 deadline.

"It's really complicated and there's no one that gives you any real guidance on it," Nick Wolfe said. "So you're kind of at their mercy."

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And what if you aren't even eligible yet? On Brexit day, Adrian Robinson, 50, a project buyer from Birmingham, will only have been registered as residing in Germany for six years and nine months, over a year shy of the required eight years. He travels a lot for his job and is concerned about his ability to move around Europe with as much ease as he has thus far.

"Whatever Mrs Merkel says about guaranteeing rights for people to stay in Germany, that's not necessarily how it will work entering or leaving the EU via another point," he says.

Robinson is also dismayed by the prospect of having to relinquish his British nationality, were he to apply once the UK has left the EU: "On an emotive level it really upsets me we are forced down this route. All I can do is hope that sense prevails, and people don't play politics with us."

Brits abroad as bargaining chips

Ingrid Taylor heads the Bavarian branch of the "British in Germany" campaign, which along with the broader "British in Europe" coalition represents UK citizens in the EU, and is awaiting the outcome of a citizenship application she submitted last November.

She speaks scathingly of the lack of support from the British government: "Because we are disenfranchised no one cares about us," she says, referring to the fact that Brits lose their right to vote in Britain after 15 years of residence abroad. "They're not going to look after our interests — because we can't vote, there's no gain in it for them."

But fast-track citizenship cannot be the sole solution, according to Jane Golding, chair of the British in Europe: "Citizenship is not a panacea for all the issues. What we've had as EU citizens is a really complex bundle of interlinked rights: your right to free movement; to residence; to equal treatment; to work; to have your qualifications recognized; all sorts of rights about pensions and healthcare, all in one bundle. And you need all of them in order to live and work and have a life in another country."

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For Golding, it's now crunch time: The bargaining-chip status of Brits in the EU must end, and rights must be guaranteed.

"We are a finite group of people who in good faith, and with legitimate expectations, thought that our rights were for life. What we are asking is that all of our rights, our complex bundle of rights are simply guaranteed."

And as the withdrawal agreement is taking much longer to draw up than hoped, they are also asking for citizens' rights to be ring-fenced for the rest of the negotiations: "Because we are people, these are people's lives, and we have been living in limbo and uncertainty for all this time."