Nah I've dipped in and out of it so not got much in the way of an answer bank in my head - this was just a combination of bad luck... and being a bit thick.
For what it's worth, I had to pay even though I moved to Sweden.
I had to inform them every year of what I earned and provide proof every bloody year. Their website, customer service and general ability to communicate and help me pay were absolutely atrocious. And awful hold music is on a 30...