For EU nationals living in Britain and wanting to legally remain after Brexit, a letter or an email was enough to clinch it. It would have been churlish then for France not to reciprocate by relaxing its almost hallucinatory bureaucratic requirements for the British in France, allowing them to do the same. And to the astonishment of all, it did relax them.

Catriona made an initial attempt to obtain a residency permit three years ago. She went for an exploratory interview at the nearest prefecture. A long wait in a squalid, packed waiting room, followed by the vituperative rudeness of the functionary traumatised her. Never again, she said. Sod that. And as recently as six months ago, an English friend who has lived in France for more than 30 years carried to the prefecture a file of documentation an inch thick and was still denied.

Just a week before Brexit Day, however, word went round that an email answering a few very basic questions would be enough for the British living in France to be given a number which could then be attached to our passports as proof of pre-settled or settled status. With this number we could come and go between the UK and the EU like yo-yos if we liked. Without it, and under the new Brexit rules, we would be allowed to stay in France for three in every six months only.

Then, I couldn’t have cared less. If the rule was applied to me I would adjust my habits accordingly. Not forgetting either that my vote to leave the EU was partly responsible for this new rule. I ought therefore to take this squarely on the chin.

Nevertheless, between Christmas and New Year I spent five minutes on the form and sent the email. Almost immediately I received a confirmation number. Most undeservedly, my life was now less complicated than it was before. Familiar with the inexorable but elephantine pace of French bureaucracy, I assumed that I could now forget about whether my status was settled, pre-settled or complete bum, and for good.

So Catriona and I were surprised to receive, a few weeks later, a joint invitation to the prefecture to settle the question of Residency once and for all. Would we please come, it said, between the hours of 8.15 and ten and bring passports and a single passport photo each. We nodded sagely to each other. Surely this was a bureaucratic shot across the bows rather than anything meaningful. Nevertheless we turned up — Catriona showing symptoms on arrival of the post-traumatic stress disorder caused by her previous visit.

At a gate in the railings a pleasant chap examined our invitations. Ah yes, he said, the prefecture was ‘doing’ the English every day, this week. Would we please follow the arrows. These led us across a cobbled courtyard to a side door to a Belle Epoch mansion. Expecting a long wait, I’d brought with us a water bottle, a packed lunch and Winston Churchill’s The World Crisis, Volume II.

We needed none of these. There was nobody waiting and four unoccupied booths to choose from. I chose one with a louche-looking young man behind the glass. Dealing only with a succession of elderly British expats for two solid days had, I think, broadened even his outlook. Behind his professional poker face he was tickled by this succession of extraordinary creatures, and all of them originating — incredibly — from not that far away. What further absurdity of appearance, speech or manner would the Englishman now standing before him come up with?

He indicated that I should shove my passport and the separate passport photo through the slot in the Perspex screen. My passport photo was a set of six identical ones taken by a machine from which he could select one. On one of the six faces, in an idle and frivolous moment, I’d overlaid with a black felt-tip pen a Hitler moustache and slanting forelock and a pair of John Lennon spectacles. I only remembered I’d done this when he singled it out as the one he would prefer to use.

Then he took my finger- and thumb- prints and said I was free to go. ‘Is that it?’ I asked, genuinely shocked. It was. A fortnight later the postman came panting to the door with two envelopes. Inside were our laminated French Residency Permits. The local expats’ permits all arrived on the same day and we were all thoroughly amazed. But as I say, for France not to have reciprocated would have appeared churlish.