I worked for a few years in a few EU28 countries. According to the principle of aggregation of periods each country will contribute to my pension.
I am only 27 and it doesn't seem likely that I am going to retire any time soon and the shape of the European Union once I retire might be very different from today. Brexit will probably happen eventually.
In the year 2060 or so, will the UK still be obligated to pay my pension, even though they are no longer part of EU?