Oh boy we have this problem too, every election cycle. We have people looking fondly to a time when we were not part of eu, they call it when we were sovereign whatever that means. But they conveniently forget you needed a visa to get everywhere and to get that you have to queue at an embassy and wait about a week or more. They forget that even making phone calls to and from roaming used to cost a fortune, hello everything was more complicated and tedious. But noo eu is so bad for paper straws and a few other stupid things I don’t want to get into. Don’t get me wrong it has its flaws but damn mist of these people complain and want out of eu while working in eu!! Talk about stupidity manifested. Anyway so far, with one exception were said stupidity manifested in the most spectacular way, most countries stay in despite all the best efforts of a certain vodka fueled country which shall remain nameless.

You are right it is not a given and it is a constant battle but in your case your system has never been tested this way. I really hope it will hold.